Ages ago long ago, sea crab farming It has become all too familiar to all of us. Because, with the advantage of “golden sea”, the Vietnamese environment is extremely suitable for raising this valuable seafood. Crab meat is rich in nutrients, adding many substances such as protein, minerals, protein, … against diseases.
So, is it too difficult to raise sea crabs and what techniques are needed to develop this model, let’s find out through our article below.
Habitat conditions of sea crabs
pH: The compatible pH for sea crab farming is between 7.5 and 9.5. Sea crab farming chooses an environment with a pH of 7.5 to 8.2 which is the most perfect.
Water temperature: Sea crabs are widely distributed in high latitudes. Their tolerance to low water temperatures is quite good. Therefore, keeping sea crabs at a water temperature of 25 to 29 degrees Celsius in the southern sea area, the crabs can adapt.
Habitat: Great places to breed sea crabs are rich in aquatic vegetation, semi-submerged areas, have shores for shelter, find burrows during molting and spawning periods.
Sea crab farming techniques
Construction of a pond to raise sea crabs
Sea crab ponds from 500 to 5000 square meters. Forms of intensive farming include: stocking, feeding, care and management.
Sea crab ponds need to be built in areas that are easy to change water thanks to tides to keep costs to a minimum.
The farming areas of the sea must have clean water sources, not polluted by public, agricultural and domestic waste, which are favorable places to raise sea crabs.
Fill the pond with soil, compact it carefully so that it does not leak, landslide, brick can be used if conditions permit.
The foot of the pond is 3 to 4 meters wide, 1.5 to 2 meters high with the highest tidal level of 0.5m.
Inside the sea crab pond, 2 to 3 m from the shore, dig a canal 3 to 4 m wide around the pond.
In the middle of the pond, there is a floating dune that is 0.2 to 0.3 meters higher than the pond water.
Barrier around the shore to prevent crabs from crossing the shore by using thin nets around or bamboo posts, ….
Depending on the acidity of the pond bottom for appropriate treatment, if the pH of the water is below 6, spread lime powder (CaCO3) for the pond bottom.
Density of sea crab farming
If small crabs, drop 3-5 fish/m2, medium-sized crabs 2-3/m2 and large crabs 0.5-1 fish/m2. Cut off the leash, slowly let go of the crabs on the edge of the bank to let them crawl into the water on their own.
By the way, this is to check the health status of the crabs: The healthy crabs will quickly run into the water, while the weak ones often lie in place or crawl slowly.
Select seed crabs
The source of crab seed for marine crab farming is mainly based on natural seed sources. The source of seed crabs is obtained from bottom rows, fishing boats in estuaries, finding and catching in the mudflats of mangrove areas.
The best way to ensure a good seed for successful sea crab farming is to buy seed crabs from the vicinity so that the crabs can be transported quickly to the breeding site.
Each crab pond should be stocked with crabs of the same size so that they grow evenly.
Management and care of sea crabs
How to feed sea crabs?
The main food is fresh food such as fish chips, crabs, fish heads, etc. The daily amount of food provided is about 4 to 6% of the weight of the crabs.
Feed sea crabs once a day from 17 to 19h. Spread the food evenly around the pond to prevent crabs from competing.
Raising sea crabs daily must pay attention to feeding the crabs, do not let the crabs starve, otherwise the big crabs will kill the small crabs that eat meat.
Sea crab farming must have food reserves.
Sanitize the crab pond
Sea crab farming must change the water regularly and check the environment to ensure the hygiene of the crabs. Sometimes, the bottom of the pond accumulates a lot of leftover, rotting food, it is necessary to drain, decanter and clean the pond bottom by scraping the mud on the surface and rotting leftovers.
Sea crab farming is hard work, it’s time to get the results. Hit the crab to check the quality. Commercial crabs must reach 250g/head or more, crabs are now meaty or full of bricks. When you see that the crabs have reached the standard, the price is good, then harvest the crabs and sell them for high economic value.
See also: Technical Guide to Farming Crab In Cement Tank