CATDOLL : CATDOLL: What kind of salt water should be used to raise swimming crabs?

What kind of salt water should be used to raise swimming crabs?

If you are raising land hermit crabs, it is best to put two water dishes in the breeding tank, one for fresh water (use mineral water, distilled water or cold boiled water, not tap water containing chlorine~), and the other for sea water for them to bathe (use calcium-added salt, the ratio of water to salt is 100ml:3g)

As for food, since hermit crabs are nocturnal animals, it is best to feed them after 10 pm and change their food every day. You can feed them with rice, bread crumbs, vegetables, fruits, etc. (I often feed them bread crumbs). In addition, they especially like to eat corn and popcorn. If they have just shed their skin, you can give them more calcium and protein food.

Water quality requirements: water temperature should be above 18℃, daily temperature difference should be less than 8℃, salinity should be 18-32, pH value should be 7.8-8.6,

Feed Type

Low-value shellfish is the best, followed by low-value fresh fish and shrimp. It is recommended to use compound feed to make up for the deficiency of natural bait. The crude protein content of compound feed is required to be above 35%, and the quality should meet the requirements of GB13078 and NY5072.

Before feeding fresh live bait, shellfish with thick shells should be crushed, and large fish and shrimp should be chopped. Note that fresh live bait should be cleaned. When feeding non-shellfish bait, shell powder should be added to the bait if conditions permit, to prevent the swimming crabs from growing slowly or having difficulty molting.

No. If it is fresh or cooked swimming crab, it is best to eat it on the same day in summer. If you can't finish it, put it in the freezer instead of the refrigerator. In winter, it doesn't need to be put in the refrigerator. Generally, it can be kept for three days. If it is canned, just refrigerate it if you can't finish it. It is best to wrap it with plastic wrap when putting it in the refrigerator to keep the crab fresh to the maximum extent.

In fact, if you have bought swimming crabs yourself, you will know what kind of water swimming crabs are raised in, salt water or fresh water. Anyway, this kind of thing is usually raised directly in sea water, so basically it is best to use salt water to relieve itching. Of course, because the composition of salt water and sea water is different...

The composition of salt water and sea water is different, so it will not last long. Therefore, it is best to eat it up as soon as possible.

What is the salinity and water temperature of swimming crabs?

Water quality requirements: water temperature should be above 18℃, daily temperature difference should be less than 8℃, salinity should be 18-32, pH value should be 7.8-8.6,

Feed Type

Low-value shellfish is the best, followed by low-value fresh fish and shrimp. It is recommended to use compound feed to make up for the deficiency of natural bait. The crude protein content of compound feed is required to be above 35%, and the quality should meet the requirements of GB13078 and NY5072.

Before feeding fresh live bait, shellfish with thick shells should be crushed, and large fish and shrimp should be chopped. Note that fresh live bait should be cleaned. When feeding non-shellfish bait, shell powder should be added to the bait if conditions permit, to prevent the swimming crabs from growing slowly or having difficulty molting.

After mating, the swimming crabs should be fed with high-quality bait rich in protein and unsaturated fatty acids (such as sandworms) to promote the gonadal development of female crabs.

Additional information:

Economic Value

The crab has a lot of meat, fat, delicious taste and rich nutrition. Every 100 grams of crab contains 14 grams of protein and 2.6 grams of fat. It is mainly eaten fresh by steaming, and can also be salted to make "choked crab" and crab sauce. The crab eggs are rinsed and dried to become "crab roe", which are all top-grade seafood.

Water temperature

The adapted water temperature is 8~31℃, and the optimal growth water temperature is 15.5~26.0℃. The activities of the three-spotted swimming crab are different in different water temperature environments. When the water temperature is below 1.5℃, it will not eat, and some individuals will freeze to death in shallow waters; when the water temperature is 0~6℃, it will not eat, burrow in the sand day and night, and be in a dormant state; when the water temperature is 8~10℃, it will stop eating, become less active, and lurk in deep waters;

At 14℃, the food intake decreases, and they begin to move to deep areas and their activities are normal; at 15~26℃, their food intake is large, their activities are normal, and their growth is fast; at 17~21℃, it is the peak mating period; at 14~21℃, egg-carrying groups begin to be found; at 12~14℃, they begin to lay eggs.

salinity

The adapted salinity is 13-38‰, and the optimal growth salinity is 20-35‰. The adapted salinity for wintering is 28-35‰. When the salinity is lower than 8‰ or higher than 38‰, the fish will stop eating and moving, and all will die after one day.

Reference: Baidu Encyclopedia - Swimming Crab

Water quality requirements for swimming crab farming: water temperature must be above 18°C, daily temperature difference must be less than 8°C, and salinity must be 18-32.

The sources of crab seedlings: There are mainly two types: fishing in natural sea areas and artificial cultivation. The seedling size is generally 80 pieces/kg. The crab seedlings are required to be uniform in size, strong in physique, with complete appendages, strong vitality, and a soft shell rate of less than 10%.

Stocking time: generally from late May to mid-June.

Water quality requirements: The water temperature must be above 18°C, the daily temperature difference must be less than 8°C, the salinity must be 18-32, the pH must be 7.8~8.6, the ammonia nitrogen content must be less than 1 mg/L of water, the dissolved oxygen must be greater than 5 mg/L of water, and the transparency must be maintained at 30~40 cm.

Stocking density: Generally, the stocking density of crab seedlings is 80-100 per acre, and the stocking density should be controlled at 1000-1500 per mu.

Additional information:

Water quality management for swimming crab aquaculture

Adjust the water quality and use fresh water for seedling raising. The water for seedling raising needs to be filled with tidal water and then subjected to secondary sedimentation before use. After the water is filled, it is disinfected with quicklime in the primary sedimentation tank to kill plankton and pathogenic bacteria. If the salinity is not suitable, the salinity should be adjusted in the water distribution tank. The salinity is preferably adjusted to 26~28‰. When the water enters the nursery pond, it is strictly filtered with dense silk screen to prevent organisms from entering the pond. The water in the nursery pond also needs to be treated with EDTA sodium salt to complex the heavy metal ions in the water. During the nursery period, according to the water quality and the different stages of the larvae, pay attention to water changes, 20~30% in the early stage and 100~150% in the later stage to keep the water fresh.

Thoroughly disinfect the nursery pools and tools. Before nursery, clean the water storage pools, nursery pools, bait pools, etc., remove dirt and sludge, rinse with clean water, and then disinfect with 100ppm bleach and 100ppm formaldehyde to kill pathogens in the gaps of the pool wall. In addition, the tools and supplies used, such as crab cages, nets, buckets, water pumps, etc., should be frequently and strictly washed and disinfected with 100ppm potassium permanganate or 100ppm bleach to prevent bacteria from entering the pool.

References:

Baidu Encyclopedia - Swimming Crab

I have a swimming crab at home. The water temperature is about 24℃ and the salinity is 2% (1.020). The bottom is covered with sand. This crab has the habit of burying in the sand. There should also be a filter, and it is best if the filter can provide oxygen.

Swimming crab Salinity and water temperature

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