WO2006042371A1

WO2006042371A1 - An aquatic-culture system

Info

Publication number: WO2006042371A1
Application number: PCT/AU2005/001632
Authority: WO
Inventors: Loy Reginal Markham; Emilio A. M. Suntay; George Chamberlain
Original assignee: Sunchamber Biotech Pty Limited
Priority date: 2004-10-21
Filing date: 2005-10-21
Publication date: 2006-04-27

Abstract

A system and method for cultivating aquatic organisms (eg crab, shrimp, prawn, fish, shellfish) and/or aquatic plants (eg seaplants, algae, microalgae), comprising at least one conditioning module (10) for conditioning cultivating medium such as sea water. The sea water is passed into cultivating modules (20/30/40) which are preferably arranged in a series to enable the staged movement or transfer of aquatic organisms under gravity flow to the next module in the series once a growth stage has been achieved. Cultivating material can be returned to the conditioning module (10) for re-conditioning, thereby providing a closed loop. The modular approach allows an area to be partitioned into three areas which multiplies the productive capacity of the system.

Description

AN AQUATIC-CULTURE SYSTEM

FIELD OF THE INVENTION

This invention relates to an aquatic-culture system for cultivating aquatic organisms, for example, Crustaceamorpha.

BACKGROUND

Aquatic-culture systems are used to cultivate aquatic organisms, for example Crustaceamorpha species (commonly referred to as shrimp/ prawn) for commercial sale. Cultivation systems currently used are highly profitable but high commercial risk operations because of the following challenges and risks.

There is a requirement for substantial input of high-quality and consistent labour to maintain and cultivate aquatic organism Crustaceamorpha species throughout their lifecycle. There is also a lack of or ineffective bio-security (i.e. ability to prevent infection of the system and Crustaceamorpha from the external environment). An outbreak of disease in aquatic-culture systems substantially reduces the population and quality of the aquatic organism and therefore the commercial viability of the aquatic- culture systems. Furthermore the lack of mechanisms and systems to counter the potentially adverse effects of faeces or secretions from the aquatic organism which increases toxicity in the systems that can further stress the aquatic organism and can result in disease, death and/ or reduced growth.

Early detection of disease in aquatic-culture systems is rare because of the fact that the condition of the aquatic organism is not easily detectable while they live in the same culture medium for many months. Hence, production and feeding continues despite the resultant reduction of aquatic organisms leading to enormous economic losses when the aquatic organisms are harvested.

Aquatic-culture systems, in general, are not environmentally friendly and wastes from aquatic-culture systems are typically transferred to the surrounding ground or natural bodies of water. High levels of nutrients including phosphorous and nitrates and organic solid wastes in the waste discharged from such systems causes damage to the ecosystems of nearby ground water systems, fresh or marine bodies of water and the coastal waters, and also reduces the commercial effectiveness of the aquatic-culture system which relies upon a source of water from those same nearby fresh or marine bodies of water and coastal waters.

In particular, these discharges can result in euthrophication of the surrounding water environment causing fish deaths and red tides which not only harms the natural environment but also the local marine communities' dependent on such bodies of water. In addition, aquatic-culture systems often contaminate ground-water with brackish, saline and nutrient-rich water causing contamination of valuable groundwater reserves much like many agricultural activities. Compounding these issues is the prevalence of many diseases from both the aquatic-culture and the wild that are caused by the use and discharge of water from one water system to the other. On the other hand, incorporating environment-friendly measures into aquatic-culture activities is costly which in turn affects its economic viability.

Aquatic-culture systems are also economically inefficient, market- inflexible, and very sensitive to climatological aberrations because of the lack of technological, managerial, and commercial unity in design of operating platform. Aquatic-culture systems are therefore in general not environmentally, socially and commercially sustainable owing to the lack of environmental- friendliness coupled with their lack of bio-security.

Accordingly, it is an object of the invention to solve or at least reduce one or more of the problems outlined for present aquatic-culture arrangements as discussed above.

Throughout the specification and the claims, unless the context requires otherwise, the word "aquatic organisms" will be understood to include any aquatic animals, plants, species, or combination thereto. Specific examples include aquatic animals such as Crustaceamorpha (e.g. crabs, shrimp/ prawn), fish (such as Centropomidae, Serranidae, or Labridae), shellfish (e.g. oysters); aquatic plants such as seaplants, algae, and macroalgae.

SUMMARY OF THE INVENTION

In one aspect of the invention there is provided an aquatic-culture system for cultivating aquatic organisms including:

(a) at least one conditioning module for conditioning an aquatic organisms cultivating medium introduced therein;

(b) one or more aquatic organism cultivating modules for containing aquatic organisms and aquatic organism cultivating medium, at least one cultivating module adapted for obtaining cultivating medium from a conditioning module;

(c) communication means for transferring either or both of the aquatic organisms and the cultivating medium from the at least one conditioning module to a cultivating module or between two cultivating modules; and

(d) a return conduit for returning at least a portion of the cultivating medium from at least one cultivating module to the conditioning module for re-conditioning said cultivating medium.

Preferably, the system further comprises a feed unit for introducing feed for the aquatic organisms into either or both of said at least one conditioning and said at least one cultivating module,

Preferably, the system further comprises at least one harvesting module f or harvesting the aquatic organisms adapted to obtain aquatic organisms and cultivating medium from the cultivating modules.

Preferably, the communication means permits transfer of either or both of the aquatic organisms and the cultivating medium from the at least one cultivating module to the harvesting module.

More preferably, the return conduit returns at least a portion of the cultivating medium from the harvesting module to the conditioning module for re-conditioning said cultivating medium.

Preferably, the communication means allows each module to be in medium communication with another module for a predetermined time thereby enabling staged movement of the aquatic organisms and cultivating medium from one module to the next in the series.

It is preferred that the communication means is in the form of a conduit having a valve for controlling the passage of either or both aquatic organisms and cultivating medium.

It is preferred that the return conduit has a pump to effect the cultivating medium return to the conditioning module.

Preferably, each module is adapted to prevent and reduce loss of cultivating medium to the external environment and to assist in maintaining temperature of the system through sealing the system so that it is water- and air-tight. In addition, the adaptation to prevent and reduce loss, assists in maintaining biological security from the external environment so as to prevent entry of elements detrimental to aquatic organisms or the quality of cultivating medium i.e. to prevent transmission of disease from the external environment to aquatic organisms or cultivating medium.

Preferably, the each module is sealed and/ or insulated from the surrounding environment and in particular from elements detrimental to the aquatic organisms or the quality of the cultivating medium.

Preferably, the aquatic-culture system is a closed system in that the system is sealed to prevent loss of cultivating medium to the surrounding environment or contamination of the system from the external environment.

It is preferred that rainfall is collected and delivered to the system to account for any water losses that may occur, for example, when harvesting the aquatic organisms. Preferably, an independent reservoir from the system is used to "top up" water in the system as required. In one example, rainfall could be directed by communication means into the harvesting or conditioning modules. Preferably, the cultivating medium introduced into the system is brackish-water or seawater which has been previously treated by exposure to UV, Ozone or Chlorine, and filtered to remove excessive particulate material. The particulate material may then be sundried and returned to the sea or disposed of in an ecologically safe manner.

Preferably, the aquatic organisms cultivated in the aquatic-culture system is Crustaceamorpha.

It is preferable that the Crustaceamorpha being cultivated is P.Monodon or other Penaeoidea species.

Alternatively, the aquatic organism cultivated in the aquatic-culture system is a fish.

Preferably, the fish are Centropomidae, Serranidae or Labridae.

Alternatively the aquatic organism cultivated in the aquatic-culture system is a shellfish such as oyster.

Preferably the conditioning module includes a marine ecosystem module adapted to receive additional elements for interaction with the cultivating medium which optimizes the conditions of the medium for growth of the aquatic organisms.

It is preferable that aquatic plants be present in the conditioning module, the aquatic plants chosen based on their ability to absorb phosphorous and nitrogen from the cultivating medium. Preferably, the marine ecosystem includes aquatic plants.

More preferably, the aquatic plants includes macro-algae and/ or micro-algae.

Preferably, the conditioning module includes a predetermined microbial population.

Preferably the desired microbial population includes a nitrifying bacteria such as a bacterial-floc culture including an effective amount of Nitrobacter and Nitrosomanos.

It is preferred that food is added to the cultivating medium within each module between ten to fifty times during a 24 hour period.

Preferably each module is cylindrical having a surface area of less than 500 square metres or a volume less than 20 mega litres. Alternatively, each module is rectangular.

Preferably the cultivating medium is free of antibiotics.

Preferably each cultivating module has a filter adapted to extract waste product from the cultivating medium.

It is preferred that the organic wastes are collected, leached of salt content by filters to enable re-use of the salt in the system. It is also preferred that the organic waste is transferred to a drying bed. Preferably the organic waste can then be used as a fertiliser or soil additive.

Preferably light transmission into the modules from the external environment is filtered, blocked or reduced to minimise growth of oxygen depleting micro-organisms, for example algae.

It is preferred that at least one module includes solar or heat absorbing material.

It is preferred that the aquatic organisms introduced into the system is pathogen free.

In the case of an aquatic-culture system having two or more modules in series for staged growth of the aquatic organisms, each successive module in the series has a larger volume than the previous module in the series to accommodate the increased mass/ size of the aquatic organisms as they mature, the volume of each module being pre-determined by the type or quantity of aquatic organisms being cultivated.

Preferably, three cultivating modules are connected in a series so that cultivating medium can flow between cultivating modules.

More preferably, successive cultivating modules in the series have a larger volume than the previous module in the series.

It is preferred that each successive module is positioned relative to the prior module in the series to enable the cultivating medium and aquatic organisms to be released under gravity flow to the successive module in the series.

Preferably the system includes three modules wherein the first, second and third modules contain a volume medium of about 500,000 litres, 4,500,000 and 9,000,000 litres respectively.

Preferably the medium within each module is agitated to suspend the food and waste particles in the cultivating medium in each module and to provide aeration of the cultivating medium within each module.

According to a second aspect of the invention, there is provided, method of cultivating aquatic organisms including:

(a) conditioning the aquatic organism's cultivating medium in at least one conditioning module;

(b) transferring cultivating medium from the cultivating module into one or more aquatic organism cultivating modules for containing the aquatic organisms;

(c) adding aquatic organisms to cultivating module; (d) transferring either or both of the aquatic organisms and the cultivating medium from the at least one conditioning module to a cultivating module or between two cultivating modules; and

(d) returning at least a portion of the cultivating medium from at least one cultivating module to the conditioning module for re-conditioning said cultivating medium.

Preferably, the method further includes the step of introducing feed for the aquatic organisms into either of both of said at least one conditioning or at least one cultivating module. Preferably, the step of transferring either or both the aquatic organisms and the cultivating medium includes transfer from the at least one cultivating module to a harvesting module.

More preferably, the method further includes harvesting the aquatic organisms from a harvesting module.

Alternatively, the aquatic organisms are harvested from the a cultivating module and/ or a conditioning module.

Preferably, the step of returning at least a portion of the cultivating medium includes returning cultivating medium from the harvesting module to the conditioning module for re-conditioning said cultivating medium.

Preferably, the transfer of either or both of the aquatic organisms and the cultivating medium uses a communication means for allowing each module to be in medium communication with another module.

Preferably, the communication means is a conduit controlled by a valve.

Preferably, the method further includes the step of pumping the cultivating medium to the conditioning module.

Preferably, the step of returning cultivating medium to the conditioning module forms a closed loop aquatic-culture system.

Preferably, the method further includes the step of collecting rainwater for use as the cultivating medium. Alternatively, the method further includes the step of providing brackish- water or seawater for use as the cultivating medium.

Preferably, the method further includes the step of treating the cultivating medium by exposing the medium to UV, Ozone or Chlorine, and the further step of filtering the medium in any order.

Preferably, the aquatic organisms are Crustaceamorpha.

More preferably, the Crustaceamorpha being cultivated are P.Monodon or other Penaeoidea species.

Preferably, the method further includes the step of controlling the condition of the cultivating medium by adding elements of a marine eco¬ system within the at least one conditioning modules.

More preferably, the marine ecosystem includes adding and/ or cultivating aquatic plants.

More preferably, the aquatic plants include macro-algae and/ or micro- algae.

Preferably, the method further includes the step of providing and/ or culturing a predetermined microbial population within the conditioning module. More preferably, the predetermined microbial population includes a nitrifying bacteria such as a bacterial-floc culture including an effective amount of Nitrobacter and Nitrosomanos.

Preferably, the method further includes the step of adding feed for the aquatic organisms and/ or the marine eco-system to the cultivating medium between ten to fifty times during a 24 hour period.

Preferably, the method further includes the step of blocking or reducing light transmission into the modules from the external environment.

Preferably, the method further includes connecting cultivating modules in a series.

More preferably, successive cultivating module in a series have a larger volume than the previous module in the series.

Preferably, the method further includes the step of positioning successive cultivating modules relative to the previous module in the series to enable either or both the cultivating medium and aquatic organisms to be released under gravity flow to the successive module in the series.

Preferably, the method further includes agitating the cultivating medium within a module.

The invention includes at least one conditioning module for conditioning cultivating medium such as sea water. The sea water is passed into cultivating modules which are preferably arranged in a series to enable the staged movement or transfer of aquatic organisms under gravity flow to the next module in the series once a growth stage has been achieved. Cultivating material can be returned to the conditioning module for re-conditioning, thereby providing a closed loop. The modular approach allows an area to be partitioned into three areas which multiplies the productive capacity of the system, e.g. 6 harvests can be made per annum assuming a 60-70 day culture period for each module. This is an improvement over global standard of 1 or 2 harvests per annum therefore the system is more economically efficient.

Throughout this specification unless the context requires otherwise, the words 'comprise' and 'include' and variations such as 'comprising' and 'including' will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that such prior art forms part of the common general knowledge.

A specific embodiment of the invention will now be described in some further detail with reference to and as illustrated in the accompanying

Figures. This embodiment is illustrative, and is not meant to be restrictive of the scope of the invention. Suggestions and descriptions of other embodiments may be included within the scope of the invention but they may not be illustrated in the accompanying figures or alternatively features of the invention may be shown in the figures but not described in the specification.

BRIEF DESCRIPTION OF THE FIGURES

The invention is now described in detail in conjunction with an illustrative embodiment shown in the accompanying drawings. Figure 1 is a diagrammatic view of the preferred embodiment of the invention; Figure 2 is a diagrammatic representation of another embodiment of the invention; and

Figure 3 is a diagrammatic representation of a cultivating module.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

The aquatic-culture system 1 in the following embodiment uses cultivating medium 2 in the form of seawater, brackish water or freshwater (after processing or conditioning) for cultivation of aquatic organisms such as Centropomidae, Serranidae or Labridae or Crustaceamorpha (preferably P.Monodon or other Penaeoidea species) and aquatic plants such as macroalgae or fungi. The type of aquatic organisms being cultivated will determine the type of water to be sourced.

Although in the preferred form the system is used to cultivate a single species of Crustaceamorpha, it could also be used to cultivate other aquatic organisms, or combinations of aquatic organisms.

In the preferred form, system 1 consists of a source of medium 2 (for example, collected rainwater or sourced from the sea or a freshwater lake). In operation, prior to entering conditioning module 10, medium 2 is fed through pipe 4 through a filter 6, such as a bag filter or sand filter to remove particulate material, (the particulate material may be returned to the sea). The filtered medium 2 is then sterilised by passing through a chamber 8 having UV, ozone and/ or chlorinating means as known by the skilled addressee. The treated or conditioned medium 2 is then released by control valve 11 to fill conditioning module 10. In this way, all medium 2 entering the system is free of elements detrimental to aquatic organisms such as pathogens and parasites which can cause disease/ death of the Crustaceamorpha for example, Monodon baculo virus (MBV).

Once the level of filtered and sterilised medium 2 reaches sensor 102, the sensor 102 activates control valve 11 to prevent further flow of medium 2 into the conditioning module 10. Preferably the conditioning module 10 includes macro-algae such as agar-agar, algins, and/ or carageenans, marine or freshwater plants <such as micro-algae, macro-algae, phytoplanktons, and/ or a desired medium conditioning microbial population. The aquatic plants are selected to absorb phosphorous and nitrogen from the medium 2. The desired microbial population conditioning the medium is a micro¬ organism floe culture containing Nitrobacter and Nitrosomanos in just a small percentage of the total population of micro-organisms but enough to regulate ammonia and nitrogen to safe culture levels which is dependent on the biomass of the system. Preferably the medium 2 is free of antibiotics.

One or more aquatic organism cultivating modules 20, 30 and 40 are fed cultivating medium 2 from either the conditioning module 10 or from other cultivating modules 20, 30 and 40.

Preferably, after settling the conditioned medium 2 in conditioning module 10, cultivating module 20 is filled with the conditioned medium 2 and then the Crustaceamorpha are introduced through opening 202 having a removable cover (not shown) into module 20. The removable cover (not shown) allows the opening 202 to be closed after the Crustaceamorpha has been introduced to maintain bioscecurity and prevent evaporation.

After feeding and culturing the Crustaceamorpha for a period of days, control valve 212 is activated to release the contents of module 20 (both Crustaceamorpha and the medium 2), preferably by gravity flow via communication means or conduit 213 into module 30. Module 30 is topped up as desired using medium 2 from the conditioning module 10. This top-up is achieved by release valve 310 releasing conditioned medium 2 through conduit 304 into module 30.

Following feeding and culturing of the Crustaceamorpha in module 30 for a number of days, control valve 312 is triggered to release the contents of module 30 into module 40 via conduit 314, which again is topped up as desired using medium 2 from the conditioning module 10. Further openings and removable covers may be provided on modules 30 and 40 (not shown; but similar to the opening 202 of module 20) to allow the introduction of Crustaceamorpha directly into modules 30 and 40 without the Crustaceamorpha having to be introduced from module 20.

Once the Crustaceamorpha have reached a commercial saleable mass, the Crustaceamorpha are transferred into a harvesting module 50, by release of valve 412 on conduit 415, where they can be harvested through harvesting chamber or conduit 502 or directly from conduit 415 in accordance with the various methods understood by the skilled addressee. The number of days in each module is dependant on the growth rate and aquatic organisms being cultivated.

By this stage, cultivating medium 2 is unsuitable for re-use in cultivating further Crustaceamorpha, therefore the cultivating medium 2 is returned to conditioning module 10 via conduit or pipe 506 where medium 2 is reconditioned for re-use in the cultivating modules 20, 30 and 40. To recirculate the used medium 2 from harvesting module 50, pump 504 is then activated to continuously feed any used medium 2 through conduit 506 back into conditioning module 10. If the level of medium 2 in the harvesting module 50 is low or empty, then control valve 11 may then be triggered to release more sterilised and filtered medium 2 into conditioning module 10. The system thereby forming a closed loop in which medium 2 is recirculated.

Preferably the modules 10, 20, 30, 40 and 50 have access means to allow occasional manual or continuous computerized monitoring, and testing of water conditions and the status or growth progression of the Crustaceamorpha. The access means can be any opening (not shown) to allow opening of a part of each module. The access can be the valves or the conduits. For example, the opening 202 of module 20 can be used as access means. It is important that such an opening is sealable to prevent evaporation of medium 2 from the system and to maintain biosecurity of the system 1. For example samples of the medium and/ or Crustaceamorpha can be retrieved for testing the Crustaceamorpha, temperature, pH, salinity and/ or nitrate levels of the medium 2.

In an alternative arrangement, any cultivating module can return cultivating medium to the conditioning module for re-conditioning. For instance, rather than harvesting the Crustaceamorpha from the harvesting module, the Crustaceamorpha could be harvested at any time from a cultivating module and then the medium could be returned to the conditioning module. This can be achieved by pumping medium back through conduits 204, 304 and 404 or by providing alternative piping and pumps.

In addition, each cultivating module 20, 30 and 40 has a filter 206, 306 and 406 respectively preferably located substantially in the module's centre where organic wastes from the feed or faeces of the Crustaceamorpha are collected and pumped through conduits 208, 308 and 408 to a purification unit 60 where it is treated so as to be ecologically safe for use as an agricultural soil fertiliser or supplement. This mechanism for releasing indigestible or excess waste and faeces is an improvement over prior arrangements and decreases toxicity in the system, thereby maintaining balance in the ecosystems of each module and substantially decreasing stress to the culture organisms like Crustaceamorpha.

In the preferred embodiment, the aquatic-culture system 1 includes: • at least one conditioning module 10 for conditioning medium 2 received from the external environment or, for reconditioning medium 2 used in system 1 and then returned via return path or conduit 506 from the harvesting module 50;

• at least one cultivating module, but preferably three cultivating modules 20, 30 and 40 for cultivating the aquatic organism, preferably

Crustaceamorpha;

• preferably at least one harvesting module 50 for harvesting the Crustaceamorpha; and

• medium communication means in the form of conduits or pipes 204, 304, 404, 412 and 506 and control valves 210, 310, 410, 212, 312, 412 and

504 for regulating the transfer of medium 2 between the modules 10, 20, 30, 40 and 50.

It would be appreciated by the skilled person that harvesting module 50 is not essential as the Crustaceamorpha could be harvested from any one of modules 20, 30 and 40, and also that the number of cultivating modules can be varied. The modules 10, 20, 30, 40 and 50 and the aquatic-culture system 1 are sealed and insulated from the external environment to preferably prevent heat loss and also to preferably prevent water loss through discharge and particularly through evaporation of water, thereby making this system more cost effective and productive particularly for larger scale modules. If evaporation occurs, this leads to an increase in salinity levels which requires constant monitoring, testing and water replacement to maintain optimal cultivation conditions for the Crustaceamorpha (all aquatic organisms require temperature and salinity control).

Sealing and insulating system 1 from the external environment not only preferably reduces evaporation and heat loss, but also prevents transmission of disease and contamination from the external environment into the System 1. AU modules are sealed and insulated against the environment. Openings are sealable to ensure that no untreated water enters the system and to minimise exposure to birds and airborne pathogens and diseases all of which are elements adverse to the condition of the aquatic organisms growing in the system.

Each of the modules 10, 20, 30, 40 and 50 are preferably manufactured from galvanised iron, aluminium, concrete or compacted soil (for larger modules) and are lined internally with geo-textiles such as High-Density PolyEthylene (HDPE) liners. Each module 10, 20, 30, 40 and 50 preferably has a depth within the range of 1.5 to 3 metres of increasing diameter or perimeter in accordance with the growing biomass of the Crustaceamorpha. If compacted soil (i.e. aquatic ponds) is used, the compacted soil is covered by liners preferably made of geo-textiles on all sides and bottom area and covered on the top by shade structures such as greenhouse covers or steel framed insulation to reduce the possibility that the contents of the module are contaminated from the external environment.

By transferring the Crustaceamorpha from module to module as they increase in size, the system allows a substantial increase in production capacity per unit area of the aquatic-culture system 1. In the preferred form, module 20 has a capacity of about 500,000 litres while modules 30 and 40 have a capacity of 4,500,000 and 9,000,000 litres respectively.

The advantage of having independent modules also allows quarantining of each module independently of the others and limits the spread of disease from one module to another rather than the entire system being infected should this occur. This also allows the infected module to be treated whilst the other modules continue to cultivate Crustaceamorpha for commercial sale.

Preferably, modules 20, 30 and 40 have agitators that simultaneously provide high levels of aeration to continuously agitate and suspend solid particles for aerobic bacterial digestion while settling undigested solid particles in a small concentrated area of the modules 20, 30 and 40. The undigested solid particles in the concentrated area form a aquatic-sludge which is passed through filters 206, 306 and 406. The aquatic-sludge contains a mixture of organic wastes which are transferred through conduits 208, 308 and 408 to a purification unit 60 where the salt content of the waste is filtered or leached out and the salt can be returned to the system to maintain salinity levels of the medium. The organic wastes are then dried and can be used as agricultural complements such as fertilizers or soil additives. In addition, the agitation or aeration can be increased or sufficient enough to optimize absorption of oxygen by medium 2.

When modules having a size less than 500 square meters surface area or a volume of 20 mega litres are used, preferably they are circular because this shape provides a smaller settling concentration area for solid particles and reduces the likelihood of anaerobic regions within the modules 20, 30 and 40. Circular shapes provide the best circulation but are not effective in larger surface areas.

As shown in Figure 1, preferably the modules 10, 20, 30, 40 and 50 are arranged vertically and horizontally in a series, spaced with conduits 204, 213, 314 and 415 between each module to enable the staged movement or transfer of medium and Crustaceamorpha under gravity to the next module in the series. This assists in reducing the energy consumption of the system. The flow from one module to another being controlled by control valves 21O₇310, 410, 212, 312 and 412. Once the Crustaceamorpha have been harvested through harvesting container 502, the medium 2 can be returned to conditioning module 10 by pump 504 through conduit 506. Although it is preferred to have a harvesting module 50, alternatively the Crustaceamorpha could be harvested from cultivating modules 20, 30 and/ or 40.

Preferably the aquatic-culture system 1 is designed to prevent or reduce transmission of sunlight to medium 2 but still allows absorption and transmission of solar heat to the aquatic-culture system 1 to heat the medium 2. Reducing transmission of sunlight will reduce the growth of algae in the aquatic-culture system 1. Algae and autotrophs compete and prevent optimal growth of beneficial micro-organisms, bacteria, and heterotrophs in the aquatic-culture system 1. Micro-organisms (e.g. bacteria) can be used within the aquatic-culture system 1 to recycle waste and produce supplementary food within the system, thereby increasing the economical value and the environmentally friendliness nature of the aquatic-culture system 1.

Food either in the form of pelletized commercial feed and/ or other supplements, is introduced into cultivating modules 20, 30 and 40 by feeding units 216, 316 and 416. The feed units can be automated. In addition, the system makes possible the high production of natural feed such as detritus. Preferably to achieve optimal growth of Crustaceamorpha, the food is introduced constantly from ten to fifty times (not limited) during every 24 hour period. This enables the Crustaceamorpha to consume more food over a longer period of time and reduce wasted feed. Efficient food consumption increases overall feed conversion to body mass of the aquatic organisms while reducing waste of feed and deterioration of water quality. Alternatively cultures/ organisms in the conditioning module 10 may provide adequate food, supplementing or obviating the need to directly introduce feed into each cultivating module 20, 30 and 40.

Figure 3 is a close up of a module (in this case module 30 for illustration purposes). Conduit 213 is in communication with module 20 (not shown) and conduit 314 is in communication with module 40 (not shown). Conduit 304 which supplies medium 2 (and aquatic organisms if desired) from conditioning module 10 can be seen in the top centre of the module. It will be understood that the conduits can be arranged differently about module 30 provided they still connect the various modules. In this illustration, module 30 is made from compacted soil and is lined with geo- textiles. The top is covered with shade structures 318 which in this instance are green-house covers. The shade structures can be any article which blocks or reduces light transmission into module 30. This structure can be of any height from the surface of the module 30 providing the option of disallowing or allowing various amounts of air to enter the module from the sides. The top of module is still exposed to sunlight therefore heat is still transferred to the module via the heat absorbing green-house covers. Other heat absorbing materials, i.e. solar panels or metal sheets could also be used to regulate the temperature within module 30. the heat absorbing materials could also cover the walls (sides) and base (bottom) of the module.

Module 30 includes agitators 320 which are shown as propellers disposed at the top of module 30. It will be understood that any means could be used to effectively agitate the medium in module 30, for example, jets, blowers or aerators. Furthermore, there may be a single agitator or a number of agitators as is desired. The agitators can be positioned at the top, bottom or side of the module, however, the BOTTOM is preferred since this assist in continuous suspension of small solid particles which aids nitrification and breakdown of solids by beneficial bacteria in the water column while depositing larger and excess solid particles in drain-filter 306 which is situated in a depressed and lowest part of the module at the bottom. The undigested and excess waste is regularly flushed through a drain-filter 306 of module 30. Drain-filter 306 prevents culture organisms from draining while allowing and collecting aquatic sludge from module 30 by a series of screens and gravitational flow. The aquatic cludge is disposed of along conduit 308.

Feed unit 316 is disposed at the top of module 30, however, may be positioned anywhere about or in module 30 which permits the transfer of feed into the module. The feed is manually fed into the unit and then released (either manually or automatically) as often as desired. In an example of operation of the system illustrated in Figure 1, batch N of Crustaceamorpha is introduced through opening 202 into module 20 and cultivated for a fixed period of days, for example, about 70 days (not limiting), after which they are then transferred to module 30 for the a further fixed period of days. After transfer of batch N to cultivating module 30, a batch N+l Crustaceamorpha is introduced into module 20 once it has been refilled with conditioned medium from conditioning module 10.

After a fixed period of days, batch N is transferred from module 30 to module 40. Batch N +1 is then transferred from module 20 to the vacated module 30 for a fixed period of days. Then module 20 is again refilled using conditioned medium 2 from conditioning module 10 and batch N+2 is then introduced into module 20 for a fixed period of days. After final culturing of each batch in module 40, the batch is then transferred to harvesting module 50 for harvesting through a harvesting machine connected to either conduit 415 or container 502. This system and process allows continuous and optimal production of Crustaceamorpha for commercial sale.

Although described as a serial process, it is possible to mix and overlap the culturing process that takes place in the cultivating modules.

At any time during the culture growth stages, medium 2 from the conditioning module 10 is used to stock, replenish, or top up any of the modules 20, 30 or 40 using control valves 210, 310 or 410 and pipes 204, 304 and 404 respectively. Control valves 210, 310, and 410 ensure that modules 20, 30 and 40 are adequately filled. Integral filters (not shown) prevent transfer of Crustaceamorpha into the conditioning module 10. In a further more economically efficient alternative arrangement of the aquatic-culture system, the same cultivating processes can be applied to multiple series of cultivating modules and/ or a harvesting module 50 illustrated in Figure 2. Other alternatives of the aquatic-culture system could include multiple conditioning modules or cultivating modules such as cages within the main cultivating, conditioning, or harvest modules.

The system is environment-friendly as it does not discharge any medium into the environment since it effectively works in a closed loop. The system does not contribute to salt-leaching and contamination of ground water. Nor does the system cause acidification of soils and is more energy efficient owing to the gravity flow and use of small pumps. Accordingly, the system is biosecure and environmentally friendly whilst being commercially viable. Preferably, pathogen free organisms are introduced into the system thereby the risk of disease introduction into the system is reduced. It uses less feed than conventional systems and includes an ability to culture natural feed in the form of detritus in the system thereby reducing the demand on valuable fish-meal protein and other valuable resources.

It is preferred that rainfall is collected to replace any water losses from the system 1. Water loss can occur for example, when filtered material is removed from the system 1, when the openings 202 are opened or when the marine animals are harvested. Either rainfall can be directed to an independent reservoir (not shown) which then can be used to top-up the system, or the rainfall can be directed to the conditioning, cultivating, or harvesting modules, however, it is preferably conditioned before use in the system. It will be appreciated by those skilled in the art that the invention is not restricted in its use to the particular application described. The system can be used to cultivate any suitable aquatic organism. The system may comprise three cultivating modules however it may comprise more or less modules as is required or desired. Neither is the present invention restricted in its preferred embodiment with regard to the particular elements and/ or features described or depicted herein. It will be appreciated that various modifications can be made without departing from the principles of the invention. Therefore, the invention should be understood to include all such modifications within its scope.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. An aquatic-culture system for cultivating aquatic organisms including:

(b) one or more aquatic organism cultivating modules for containing aquatic organisms and aquatic organism cultivating medium, at least one cultivating module adapted for obtaining cultivating medium from a conditioning module; (c) communication means for transferring either or both of the aquatic organisms and the cultivating medium from the at least one conditioning module to a cultivating module or between two cultivating modules; and (d) a return conduit for returning at least a portion of the cultivating medium from at least one cultivating module to the conditioning module for re-conditioning said cultivating medium.

2. An aquatic-culture system according to claim 1, wherein the system further comprises a feed unit for introducing feed for the aquatic organisms into either or both of said at least one conditioning and said at least one cultivating module,

3. An aquatic-culture system according to claims 1 or 2, wherein the system further comprises at least one harvesting module for harvesting the aquatic organisms adapted to obtain aquatic organisms and cultivating medium from the cultivating modules.

4. An aquatic-culture system according to claim 3, wherein the communication means permits transfer of either or both of the aquatic organisms and the cultivating medium from the at least one cultivating module to the harvesting module.

5. An aquatic-culture system according to claims 3 or 4, wherein the return conduit returns at least a portion of the cultivating medium from the harvesting module to the conditioning module for re-conditioning said cultivating medium.

6. An aquatic-culture system according to any one of claims 1 to 5, wherein the communication means allows each module to be in medium communication with another module for a predetermined time thereby enabling staged movement of either or both the aquatic organisms and cultivating medium from one module to another.

7. An aquatic-culture system according to any one of claims 1 to 6, wherein the communication means is a conduit having a valve for controlling the passage of with or both aquatic organisms and cultivating medium.

8. An aquatic-culture system according to any one of claims 1 to 7, wherein the return conduit has a pump to effect the cultivating medium return to the conditioning module.

9. An aquatic-culture system according to any one of claims 1 to 8, wherein each module is sealed against entry of elements detrimental to aquatic organisms or the quality of cultivating medium.

10. An aquatic-culture system according to any one of claims 1 to 9, wherein the aquatic-culture system is a closed loop system.

11. An aquatic-culture system according to any one of claims 1 to 10, wherein the conditioning module contains collected rainwater.

12. An aquatic-culture system according to any one of claims 1 to 10, wherein the conditioning module contains brackish-water or seawater.

13. An aquatic-culture system according to any one of claims 1 to 12, wherein cultivating medium is conditioned by exposure to either UV, Ozone or Chlorine, and by filtration.

14. An aquatic-culture system according to any one of claims 1 to 13, wherein the aquatic organisms cultivated in the aquatic-culture system are Crustaceamorpha.

15. An aquatic-culture system according to claim 14, wherein the Crustaceamorpha being cultivated are Penaeoidea species.

16. An aquatic-culture system according to any one of claims 1 to 15, wherein the conditioning module includes a marine ecosystem adapted to receive additional elements for interaction with the cultivating medium.

17. An aquatic-culture system according to claim 16, wherein the marine ecosystem includes aquatic plants.

18. An aquatic-culture system according to claim 17, wherein the aquatic plants includes macro-algae.

19. An aquatic-culture system according to any one of claims 1 to 18, wherein the conditioning module includes a predetermined microbial population.

20. An aquatic-culture system according to claim 19, wherein the desired microbial population includes a nitrifying bacteria.

21. An aquatic-culture system according to any one of claims 1 to 20, wherein the modules containing aquatic organisms have food added to the cultivating medium within each module between ten to fifty times during a 24 hour period.

22. An aquatic-culture system according to any one of claims 1 to 21, wherein each module is cylindrical having a surface area of less than 500 square metres or a volume less than 20 mega litres or rectangular if module has a surface are of more than 500 square metres or a volume of more than 20 mega litres.

23. An aquatic-culture system according to any one of claims 1 to 22, wherein each cultivating module further contains a filter adapted to extract waste product from the cultivating medium.

24. An aquatic-culture system according to any one of claims 1 to 23, wherein light transmission into a module from the external environment is blocked or reduced.

25. An aquatic-culture system according to any one of claims 1 to 24, wherein at least one module further includes solar or heat absorbing material arranged to control temperature of the cultivating medium therein.

26. An aquatic-culture system according to any one of claims 1 to 25, wherein three cultivating modules are connected in a series so that cultivating medium can flow between cultivating modules.

27. An aquatic-culture system according to claim 26, wherein successive cultivating modules in the series have a larger volume than the previous module in the series.

28. An aquatic-culture system according to either claims 26 or 27, wherein each successive cultivating module is positioned relative to the previous module in the series to enable either or both the cultivating medium and aquatic organisms to be released under gravity flow to the successive module in the series.

29. An aquatic-culture system according to any one of claims 26 to 28, wherein a first module contains approximately 500,000 litres of cultivating medium, a second module contains approximately 4,500,000 litres of cultivating medium and a third modules contains approximately 9,000,000 litres of cultivating medium.

30. An aquatic-culture system according to any one of claims 1 to 29, wherein the cultivating medium within a module is agitated.

31. A method of cultivating aquatic organisms including: (a) conditioning the aquatic organism's cultivating medium in at least one conditioning module;

(b) transferring cultivating medium from the cultivating module into one or more aquatic organism cultivating modules for containing the aquatic organisms; (c) adding aquatic organisms to cultivating module;

(d) transferring either or both of the aquatic organisms and the cultivating medium from the at least one conditioning module to a cultivating module or between two cultivating modules; and (d) returning at least a portion of the cultivating medium from at least one cultivating module to the conditioning module for re-conditioning said cultivating medium.

31. A method of cultivating aquatic organisms according to claim 30, wherein the method further includes the step of introducing feed for the aquatic organisms into either of both of said at least one conditioning or at least one cultivating module.

32. A method of cultivating aquatic organisms according to either claim 30 or 31, wherein the step of transferring either or both the aquatic organisms and the cultivating medium includes transfer from the at least one cultivating module to a harvesting module.

33. A method of cultivating aquatic organisms according to claim 32, wherein the method further includes harvesting the aquatic organisms from a harvesting module.

34. A method of cultivating aquatic organisms according to claim 32 or 33, wherein the step of returning at least a portion of the cultivating medium includes returning cultivating medium from the harvesting module to the conditioning module for re-conditioning said cultivating medium.

35. A method of cultivating aquatic organisms according to any one of claims 30 to 34, wherein the transfer of either or both of the aquatic organisms and the cultivating medium uses a communication means for allowing each module to be in medium communication with another module.

36. A method of cultivating aquatic organisms according to claim 35, wherein the communication means is a conduit controlled by a valve.

37. A method of cultivating aquatic organisms according to any one of claims 30 to 36, wherein the method further includes the step of pumping the cultivating medium to the conditioning module.

38. A method of cultivating aquatic organisms according to any one of claims 30 to 37, wherein the step of returning cultivating medium to the conditioning module forms a closed loop aquatic-culture system.

39. A method of cultivating aquatic organisms according to any one of claims 30 to 38, wherein the method further includes the step of collecting rainwater for use as the cultivating medium.

40. A method of cultivating aquatic organisms according to any one of claims 30 to 38, wherein the method further includes the step of providing brackish-water or seawater for use as the cultivating medium.

41. A method of cultivating aquatic organisms according to any one of claims 30 to 40, wherein the method further includes the step of treating the cultivating medium by exposing the medium to UV, Ozone or Chlorine, and the further step of filtering the medium in any order.

42. A method of cultivating aquatic organisms according to any one of claims 30 to 41, wherein the aquatic organisms are Crustaceamorpha.

43. A method of cultivating aquatic organisms according to claim 42, wherein the Crustaceamorpha being cultivated are Penaeoidea species.

44. A method of cultivating aquatic organisms according to any one of claims 30 to 43, wherein the method further includes the step of controlling the condition of the cultivating medium by adding elements of a marine eco- system within the at least one conditioning modules.

45. A method of cultivating aquatic organisms according to claim 44, wherein the marine ecosystem includes adding aquatic plants.

46. A method of cultivating aquatic organisms according to claim 45, wherein the aquatic plants includes macro-algae.

47. A method of cultivating aquatic organisms according to any one of claims 30 to 46 wherein the method further includes the step of providing a predetermined microbial population within the conditioning module.

48. An method of cultivating aquatic organisms according to claim 47, wherein the predetermined microbial population includes a nitrifying bacteria.

49. A method of cultivating aquatic organisms according to any one of claims 30 to 48 wherein the method further includes the step of adding feed for the aquatic organisms to the cultivating medium between ten to fifty times during a 24 hour period.

50. A method of cultivating aquatic organisms according to any one of claims 30 to 48, wherein the method further includes the step of blocking or reducing light transmission into the modules from the external environment.

51. A method of cultivating aquatic organisms according to any one of claims 30 to 50, wherein the method further includes connecting cultivating modules in a series.

52. A method of cultivating aquatic organisms according to claim 51, wherein successive cultivating module in a series have a larger volume than the previous module in the series.

53. A method of cultivating aquatic organisms according to either claims 51 to 52, wherein the method further includes the step of positioning successive cultivating modules relative to the previous module in the series to enable either or both the cultivating medium and aquatic organisms to be released under gravity flow to the successive module in the series.

54. An method of cultivating aquatic organisms according to any one of claims 30 to 53, wherein the method further includes agitating and aerating the cultivating medium within a module.

55. An aquatic-culture system according to any one of claims 1 to 8, wherein each module is insulated against entry of elements detrimental to aquatic organisms or the quality of cultivating medium.

56. An aquatic-culture system according to any one of claims 1 to 8, wherein each module is sealed and insulated against entry of elements detrimental to aquatic organisms or the quality of cultivating medium.

57. An aquatic-culture system according to any one of claims 1 to 13, wherein the aquatic organisms cultivated in the aquatic-culture system are Centr opomidae .

58. An aquatic-culture system according to any one of claims 1 to 13, wherein the aquatic organisms cultivated in the aquatic-culture system are

Serranidae.

59. An aquatic-culture system according to any one of claims 1 to 13, wherein the aquatic organisms cultivated in the aquatic-culture system are Labridae.

60. An aquatic-culture system according to claim 15, wherein the Crustaceamorpha being cultivated are P.Monodon.

61. An aquatic-culture system according to claim 17, wherein the aquatic plants includes micro-algae.

62. An aquatic-culture system according to claim 20, wherein the desired microbial population includes a bacterial-floc culture including an effective amount of Nitrobacter and Nitrosomanos.

63. An aquatic-culture system according to any one of claims 1 to 21, wherein each module is rectangular having a surface area of greater than 500 square metres or a volume more than 20 mega litres.

64. A method of cultivating aquatic organisms according to claim 32, wherein the method further includes harvesting the aquatic organisms from a cultivating module.

65. A method of cultivating aquatic organisms according to claim 32, wherein the method further includes harvesting the aquatic organisms from a conditioning module.

66. A method of cultivating aquatic organisms according to any one of claims 30 to 41, wherein the aquatic organisms are Centropomida.

67. A method of cultivating aquatic organisms according to any one of claims 30 to 41, wherein the aquatic organisms are Serranidae.

68. A method of cultivating aquatic organisms according to any one of claims 30 to 41, wherein the aquatic organisms are Labridae.

69. A method of cultivating aquatic organisms according to claim 43, wherein the Crustaceamorpha being cultivated are P.Monodon.

70. A method of cultivating aquatic organisms according to any one of claims 30 to 43, wherein the method further includes the step of controlling the condition of the cultivating medium by cultivating elements of a marine eco-system within the at least one conditioning modules.

71. A method of cultivating aquatic organisms according to claim 45, wherein the aquatic plants include micro-algae. 632

38

72. A method of cultivating aquatic organisms according to any one of claims 30 to 46 wherein the method further includes the step of cultivating a predetermined microbial population within the conditioning module.

73. A method of cultivating aquatic organisms according to claim 48, wherein the desired microbial population includes a bacterial-floc culture including an effective amount of Nitrobacter and Nitrosomanos.

74. A method of cultivating aquatic organisms according to any one of claims 30 to 48 wherein the method further includes the step of adding feed for the eco-system to the cultivating medium between ten to fifty times during a 24 hour period