These fish have highly valued because of their excellent body texture and flavor. The export market for grouper is rapidly increasing specially in Hong Kong, and Singapore, Japan.
The biggest challenge in commercial production of grouper fish is the shortage of fingerlings or seed from the wild or hatchery (nurseries). Because of seed shortage, high market value of this fish have encouraged many countries in Asia including India to initiate research and development programs on grouper breeding and seed production.
In India, until now, naturally collected seed from wild waters are serving the purpose. Grouper fishes are extensively cultured in coastal brackish water ponds and floating, fixed net cages in many south Asian countries.
Grouper fishes are naturally low in calories and high in proteins. Grouper fishes are great source of vitamins and minerals.
Local Names of Grouper Fish in India:- Panini been, Caravan (Tamil), McQueen, Álava (Malayalam), MRI menu, Copra, Guru (Kannada), MRI menu (Telugu), Law veto (Bengali). At this point of time, floating nursery cages with mesh size of 1.5 to 2.0 cm should be made of polyethylene netting supported by wooden frame.
These should be kept afloat with metal drums, anchored with concrete blocks and should be stocked with 250 to 600 frying or fingerlings. Once fry or fingerlings reach 15 to 20 cm in total length, they should be transferred and stocked in net cages or brackish water ponds.
The site selected for net-cage culture should be free from predators and strong wind and waves. Construction of Net Cages in Grouper Fish Farming: In net-cage culture, floating cages are built with bamboo poles and polyethylene netting material at 25 to 50 mm diameter.
Generally, these net cages are secured to bamboo poles (raft structure) buy ropes or wires. Buoyancy should be provided by empty plastic gallons attached to the bamboo frames.
Stocking in Grouper Fish Farming: The ideal water temperature for grouper fish farming should range from 27 °C to 30 °C and dissolved oxygen content at 5 mg/l. Commercial fish farmers should go for water testing to maintain optimal techno parameters.
Generally fingerlings of grouper fish with length of 12-15 cm (which are being raised in nurseries) are stocked in net-cages @ 45-50/sq. Yield in Grouper Fish Farming: A net cage of 5 meter x 5 meter x 3 meter (Length, Width and Height of the net cage) can yield up to 600 kg in about 7 months from stocking period assuming that the fishes weighing 600 grams are being harvested (collected).
The optimal techno parameters such as salinity, temperature should be maintained in the pond. The ideal salinity of 330 mg/l and temperature range 16-32 °C should be maintained in pond culture of grouper fish.
When it comes to pond size, generally it varies from 0.2 ha to 0.3 ha in area with a height of 1.5 meter to hold the water level with support of concrete dike. Generally in open pond system, green algae are formed because of sunlight and this needs to be removed frequently.
· A high-value species with great demand in the local and export markets · With prudent pond management, grouper is easier to culture than shrimp, without the attendant disease problems · Wild and captive grouper bloodstock spawn year round, hence, fry are available anytime of the year · The technology of cage culture is relatively cheap and easy to run · Culture can be done in ponds or cages Grouper is a high-value species like tiger shrimp, and with prudent pond management, grouper is easier to culture without the attendant disease problems with prudent pond management.
Shrimp farmers seeking alternative crops have found one in grouper. In addition, grouper fry or “tiny” need to be nursed first and must be regularly sorted and size-graded.
Rectangular net cages supported by bamboo poles and installed inside the pond can serve as nursery. In addition to tilapia, chopped trash fish and/or a formulated feed for carnivorous species may be given to grouper.
Regular monitoring and water changes are part of the pond routine for taking care of the stock. Grouper takes 5-7 months to attain a market-size of 400-800 g. If marketed live, fish farmers need to install temporary nets and tanks where grouper can be held while awaiting buyers and the completion of live packing for transport.
Stock adult tilapia at 5,000 to 10,000 per ha; its fingerlings will later serve as food for grouper. (3) Install 50-watt incandescent, hover-type lamp in every cage, about a foot above the waterline, to attract mys ids, cope pods, and other young fishes and crustaceans at night.
These are live food for the grouper fry, although they may also be given finely-chopped trash fish and/or mys id shrimps or “blaming.” (4) Sort and grade the fry weekly to minimize competition for space and food and prevent cannibalism.
There may be a need to feed more, so give chopped trash fish at the rate of 5% of grouper biomass per day. Place half in a feeding tray for monitoring purposes, and broadcast the rest.
(7) Do the routine pond activities: monitor water parameters (dissolved oxygen, salinity, temperature, depth), change water as the tide dictates, take weight-length measurements of some stock so that feeding can be adjusted. Provide shelters like sawed-off bamboos or PVC pipes in the middle of the net.
Carefully lift the net in early morning when most of the grouper hide themselves there. Take only the biggest fishes and transfer to a pre-installed net that is 4 × 8 × 1.5 m with 1-2 cm mesh size.
Costs-and-Returns Revenue 1,512 kg 280 423,360Variable costs natural food productionChicken manure 1,000 kg 1.00 per kg 1,000For predator eradicationHydrated lime 200 kg 1.50 300Ammonium sulfate (21-0-0) 40 kg 5.00 200Netcages for tiny (2 units, 4 × 2 × 1.5 m)Nylon nets 60 m 30.00 1,800 get cages for harvesting(4 units, 8 × 4 × 1.5 m)Nylon nets (‘A’ size) 224 m 30.00 6,720Bamboo (whole length for horizontal and vertical bracing 4 PCs 50.00 200Monofilament # 180 2 kg 50.00 100Tilapia (100 g) 4,500 PCs 10.00 45,000 Grouper tiny (1 inch) 4,500 PCs 15.00 67,500Trash fish 5,783 kg 10.00 57,830Technician’s salary 8 months 4,000 32,000Power (lights, pump, standby aeration) 20,000Subtotal 232,000Fixed costDepreciation of paddle wheel aerator 5,000Total cost 237,000Net income per run 185,710Net income per year (2 runs per year) 371,420Income tax (35%) 129,997Net income after tax 241,423 Production data Pond area0.9 number of stock4,500 survival rate80%Culture period5 to 7 monthsNumber of cropping per year1Total harvest1,512 average body weight at harvest450 selling priceP280.00/kg Marine cage culture of Grouper Attach floats (plastic drums, barrels) and sinkers or anchors (concrete blocks, etc).
Place hides and shelters inside the net cage; these may be made of sawed bamboo tied in triangular bundles. Install hover-type lamp to attract cope pods and other young fishes and crustaceans; these can be eaten by the grouper.
(Once you entered your e-mail address, you need to log in to your e-mail account and click the link to confirm your subscription). You might want to know more information about grouper aquaculture as this food fish is not only caught in the sea anymore as now it can be farm easily.
Thus, to supply great amount of this food product, then people try to develop easier method that they can use to provide more for the market. This is the reason why aquaculture is chosen to create the product that they need in higher quality with easier method possible.
To start the grouper aquaculture, the first thing that the farmer needs to do is to breed the fingerlings in the area that they provided. So the farmer will put at 100 amounts of fingerlings on each of the square meter of the pond.
Then when the fingerling is living inside this nursery pond, the farmer will give them frozen fish to eat. Then the farmer would then add some buoyancy from plastic gallons material which will then be attached to the bamboo poles.
This is the reason why the farmers that uses net cage as their aquaculture type will do some check especially for the water quality so the parameters would all be optimal. For the expected grouper aquaculture result actually highly depends on to the location where the farmer put net cage and of course the other factor for example the food as well as water quality.
On this growing place, then the farmer will need to closely attend on the pond density level. Then the bottom part of pond will be leveled since then it will get easier for the farmer to harvest their grouper fish in the end.
The farmer should also able to take care the water so it will flow continuously and still in the good parameters. Then for the water parameters itself are actually a little different from the previous grouper aquaculture type.
This is the reason the farmer will also remove the algae out frequently to ensure that the grouper aquaculture is done properly so the result is amazing.