Fish Farming FAQ/Frequently Asked Questions.
you can find here most commonly asked questions about fish farming/ fish farming faq.
Fish farming FAQ # 1: How do we farm fish?
Different species of fish seeds are brought and are commercially raised in tanks or artificially constructed structures for food. The entire procedure for farming fish takes several months, depending on the type of fish being raised. Facilities like feed and other environmental conditions are monitored regularly while farming fish and the details of the fish farming process can be read at Fish Farming.
Fish farming FAQ # 2: What is aqua farming and why is it so important or what are its advantages and disadvantages?
Aquaculture or aqua farming refers to the fact of raising water organisms like fish, crustaceans, molluscs, algae, aquatic plants, etc. aquaculture is important because it helps in food production, restores natural habitat, helps rebuild the threatened species and replenishes the wild species.
Some advantages and disadvantages of aqua farming could be:
- Source of income for the rural population
- The ability to recycle waste from poultry farm as this is used as fish feed
- Source of revenue to the state and country
- Farming can transfer diseases to wild species
- Pollutes some water systems
- Sometimes unpredictable business because of prevailing risks due to diseases, predators, weather etc.
Fish farming FAQ # 3: What types of fish are farm raised?
Fishes that can be raised in undrainable ponds in India are the Indian Carps such as rohu, catla and Mrigal and Chinese carps such as silver carp, common carp and grass carp. Other species like catfish, murrels, tilapia, mullet etc are also farmed in India. Around the world one can find carp, tilapia, salmon and catfish being farmed commonly among all the species.
Fish farming FAQ # 4: What are the common edible fish found in India?
Edible fish in India can be divided into categories where they are found such as:
- Fresh water fish – carp, catla, rohu
- Catfish – Mystus, hilsa, Bombay duck
- Marine fish – pomfrets, salmon, sardines
- Brackish water fish – mullet, pearl spot
Fish farming FAQ # 5: What is polyculture in fisheries?
This term refers to raising different species of fish together in the same pond. This is practically done to better utilize the resources available and increase the production of the farm. Generally fish that do not compete for food or have different food habits are raised together. This practice sometimes helps improve the pond environment due to the presence of different species of fish in it.
Fish farming FAQ # 6: What is integrated fish farming?
Raising other livestock or cultivating crops in combination with fish farms is called integrated fish farming. This is of importance because the animal waste or crop waste is used as feed for fish. Sometimes due to land constraints people start this technique of farming. It helps in efficient utilization of available resources like water, land, energy etc.
Fish farming FAQ # 7: What are the advantages of composite fish culture?
Composite fish culture is polyculture, where different fish species are raised together. Some advantages are:
- High production from the farms
- Effective Utilization of feed
- The quality and variety of fish produced is high
- Low mortality rate
- Better profits
Read: Composite Fish Culture.
Fish farming FAQ # 8: How does fish farming cause eutrophication?
Eutrophication is a term which indicates the presence of excess nutrients in water bodies like lakes, ponds, pools or artificially constructed structures, which causes conditions like algal blooms, etc. When fish are raised in these water bodies, not all the feed given to them is consumed. The uneaten food changes the organic composition of the water bodies and alters their oxygen levels thereby causing eutrophication.
Fish farming FAQ # 9: How can one start a fish farming business?
To start a fish farming business, there are some basic rules to follow such as investigate about the most commonly farmed fish, procure the necessary equipment and resources for the farm, applying for a subsidy if available, understanding the local market, investment required and most importantly one should know how to farm fish, their needs, climatic conditions, fish seed availability etc. For beginners detailed information about all these necessary things is available for reference at Fish Farming Business Plan.
Fish farming FAQ # 10: How much does a fish farmer make a year?
This typically depends on the type of fish being farmed. For e.g. if carps are raised in 1 acre of land then on an average the expected income annually is around Rs 1,10,000. Similarly, murrels earn different income; tilapia gets different income annually for the farmers. For reference Murrel fish farming investment and profit analysis can be read at Murrel Fish Farming Project Report.
Fish farming FAQ # 11: What is induced breeding of fish or what is hypophysation?
The pituitary gland from a mature fish is collected and homogenized in distilled water. This is then centrifugated and a hormone is injected. The extract from this pituitary is then introduced into the body of other fish like carps, which get excited and lay eggs in the pond. In short, it can be addressed as artificially inducing the hormone to help the fish fertilizer is called as induced breeding.
Fish farming FAQ # 12: What is hapa in fisheries?
Hapa is a cage made of fine mesh material and is set up in a fish farm using bamboo poles to raise fish of small size. These are created in shallow water bodies, where the flow of water is low. This type of cage formation makes it easy for harvesting and is durable.
Fish farming FAQ # 13: What is breeding hapa?
It is enclosed like a box made of meshed mosquito net material and erected through bamboo poles fixed in the pond or pool. Generally the hapa are covered with plain cloth over the top, but breeding hapa has an open top for inserting and removing brood fish. The minimum dimensions of a breeding hapa are 2 x 1.5 x 1 m. The breeding hapa is filled such that there are two male fish for one female fish. Once the eggs get hardened and embryo twitches, the brood fish are removed from that place without harming the eggs.
Fish farming FAQ # 14: What is hatching hapa?
This structure has double walls. The outer wall is made of muslin cloth and the inner wall is made of round meshed mosquito net material. The dimension of the outer wall is 1.5 x 1 x 1 m and the inner wall minimum dimensions are 1 x 0.75 x 0.75 m. The eggs from the breeding area are shifted to hatching hapa and are uniformly spread here. The minimum time for hatching is 18-24 hours. When the hatchlings get out of the inner area, the mesh is carefully removed to dispose the egg shells.
Fish farming FAQ # 15: What are a rearing pond and a nursery pond?
Rearing pond is an area within a big fish farm where fry fish from the breeding ponds are transplanted to grow into fingerlings. It contains fertile soil and should have a minimum depth of 60-80 cm with 1.5 m of depth near the floodgate. The water in this pond should be changed every 10 days. Ponds where spawns are raised up to fry fish stage are known as nursery ponds.
Fish farming FAQ # 16: What is stocking of fish and what is the density of stocking fish?
Fish are raised in a hatchery and then released into water bodies so as to supplement the present population or to create a new population of fish. Generally stocking is done for commercial benefits, but sometimes it is also useful in restoring the threatened species of fish. The minimum stocking density is for all different species of fish are different and it also depends on the size of the fish. For e.g. if the size of silver carp is 7-10 cm, then the stocking density is 3000 fish per hectare. Similarly for Mrigal fish of the same size the stocking density is 500 fish per hectare.
Fish farming FAQ # 17: What is fish seed production?
The eggs of the fish or the fry stage of the fish are called fish seeds. These are generally obtained or are produced on the farm. The later is difficult because extreme care and excellent conditions are required for the fish to spawn. There is a high mortality rate involved in producing and hatching the eggs. So, large fish farms obtain the fish seed from outside or naturally occurring areas.
Fish farming FAQ # 18: What is the cost of fish seeds?
The cost of fish seed for commercial fish farms may differ depending on the type of fish. For e.g. rohu fish seed has a minimum cost of Rs 0.75 per piece. Carp seeds and Murrel seeds may cost around Rs 3 per piece.
Fish farming FAQ # 19: How do fish get to a pond for farming?
For the fish to be farmed, the eggs are collected from the wild and brought into the farm. This method is used for fish species which have uncontrolled spawning behaviour or if artificial propagation is costly. For other species which have good spawning behaviour, the breeding is done within the farm using mature fish and hormone technology.
Fish farming FAQ # 20: How do you breed a fish?
Every fish species has its own breeding behaviour and they are not similar to others. Some general methods for breeding in fish are:
- Male and female adult fish of the same species are picked up and are placed into a spawning area; proper feed and environmental conditions are maintained within the zone.
- If necessary stimulating the rainy season effect for the fish is beneficial.
- Once the eggs are produced, they should be carefully handled.
- Generally large farms use induced breeding to produce eggs or make the fish spawn.
Fish farming FAQ # 21: How many eggs does a fish lay?
A female fish of 1 kg weight can approximately lay 1.5 lakh eggs at a single time. This value again depends on the type of fish, its breeding conditions and its weight at the time of breeding. All species have a different egg laying capacity.
Fish farming FAQ # 22: How long does it take for a baby fish to hatch?
In cold weather conditions, spawning takes longer time otherwise the minimum time required to hatch an egg is 40-72 hours under warm conditions. Even after the eggs hatch, they carry a yolk sac around them, which gets absorbed in 3 or 4 days.
Fish farming FAQ # 23: What is a brood fish?
These are the mature fish specially used for breeding purposes. They are generally kept under controlled environmental conditions such that they produce quality eggs. This category of fish is used to enhance fry and seed production numbers.
Fish farming FAQ # 24: What is feed conversion ratio?
This is a value which indicates the farmer about the feed required by the fish during its growing cycle. In a much simple way it can be explained as the amount of feed required to grow 1 kg of fish. It is a value that determines the profitability of a fish farm.
Fish farming FAQ # 25: What kind of feed is given to farmed fish?
Mash feed is a popular and widely used fish feed in India. The main ingredients of the feed include de-oiled rice bran, groundnut cake and cotton seed cake. Pellet feed, which is a commercial variety of feeds available in the market, can also be used. Supplementary feed along with the natural feed must be given to the fish for faster growth. Natural feed can be plankton, basal organic elements, small aquatic insects, grasses, rotten plants and animals, etc. supplementary feed can be crop grains, blood of birds and animals, maize powder, dried molasses, sesame cake etc.
Fish farming FAQ # 26: How often do you feed fish in fish farms?
Each species of fish has a different feeding habit and behaviour; also it is dependent upon the stage of the fish. At the larvae stage rice barn and groundnut oil cake in the ratio 1:1 are given for 15 days so as to produce fry fish of 300 g weight and 15-25 cm length. Similarly, at the fingerling stage and fully grown stage, the ratio of feed is increased. The feeding methods can be studied in detail at Fish Farming Business Plan.
Fish farming FAQ # 27: What is catfish farming and is catfish farming profitable?
Catfish is a species of fish generally farmed for its multiple benefits. It is a hard variety and is considered to survive in all types of regions especially the warmer areas. This variety of fish has great demand for its rich and important source of protein; hence it would definitely be a profitable business.
Fish farming FAQ # 28: How long does it take to raise a catfish?
Catfish needs approximately 18-24 months to grow to a size of 1 pound. This is the maximum size it can grow, but during commercial fish farming depending upon the demand in the local market, they are not allowed to grow to such great weight.
Fish farming FAQ # 29: What are the different methods of preserving fish?
Fish can be preserved by the following methods:
- Corning is applying salt to the belly and the skin of the fish and putting it in the container by wrapping a damp cloth.
- The fish are rolled in salt and packed in glass containers in a layer format.
- Fish can be dried to preserve them.
- Smoking the fish can store it for a longer time.
- Canning the fish using preservatives can improve their shelf life.
Fish farming FAQ # 30: Can aquaculture damage the environment?
Yes, sometimes excess nutrients left within the water bodies can damage the balance of environmental conditions due to eutrophication. The major harm is from farms which are built on large water bodies. Cages are built to farm fish, but the waste from the fish escapes into the water causing pollution. These wastes from fish may contain toxics and antibiotics, which are harmful to other living organisms on earth
Fish farming FAQ # 31: What is re-circulating in aquaculture/Pisciculture systems?
This is a method by which exchange of water is minimised due to use of bio-filtration and other environmental control techniques to recycle the used water. The water is treated with a series of processes such that the need for fresh, clean water is reduced to maintain fish or other aquatic stock in the farms. Some of the measures in the re-circulating of water involve bio-filtration, solid removal, oxygenation, pH control, temperature control and bio-security.
Fish farming FAQ # 32: What causes fungus in fish tanks?
Fungus can develop within the tanks or fish farms due to several reasons such as poor water quality, low maintenance of the farms, improper hygiene, un-noticed diseased or injured fish in the pool, dead fish which start decomposing etc. cleaning the fish farming tanks or areas and disinfecting them properly is a necessity to control fungus within the tanks or pools.
Fish farming FAQ # 33: What causes brown blood disease in fish and how is it dealt with?
Excess nitrate levels in water bodies where fish are farmed cause brown blood disease. It can be also be addressed as nitrate poisoning because the nitrate in water oxidizes the hemoglobin in the fish blood cells and converts it into a compound called methemoglobin. This compound obstructs the oxygen intake due to which the fish in water experience oxygen stress and die immediately. Administering proper antibiotics can help overcome this problem, but most importantly care should be taken such that the disease doesn’t occur.
Fish farming FAQ # 34: What is a fish handler’s disease?
This disease is addressed with many names such as fish poisoning, erythema migrans, sealer’s finger, whale finger, bubble finger, fish hand, fish handler’s disease etc. it affects the people who handle the fish and their wastes. The incubation period for the bacteria is 1-7 days and the symptoms are fever, pain in muscles and joints, sometimes internal infection may occur in the nervous system and heart, bluish-purple spots etc. Commonly it is observed on the hands. Any cut or small opening on the skin surface can cause the bacteria from fish to enter the body, but the bacteria has an inability to proliferate in the warm body conditions and remains confined to the affected area causing itching, pain and swelling. Antibiotics can help relieve the problem.
Fish farming FAQ # 35: What are the sources of nitrate in ponds and water bodies and how are the levels of nitrate reduced in a fish tank?
Nitrate in water is formed by the breaking of ammonia compounds through bacterial activity. Nitrate is the waste product of these bacteria, which feed on ammonia based food. Using sodium chloride is a solution to decrease the nitrate concentration in water. Mainly the chloride in common salt helps the fish to absorb fewer nitrates thereby causing less poisoning. Preventing this solution is more important that treating the fish already stressed with the toxicity.
Fish farming FAQ # 36: How does ammonia affect the fish?
Oxygen is the first important parameter needed in water for fish, the second important thing needed is ammonia, but in limited amounts. Too less ammonia in water can cause stress in the fish, make them more susceptible to bacterial infections and damage their gills. Lack of sufficient ammonia in water can lead to poor growth in fish and make it difficult for them to handle routine activities. Excess ammonia can introduce heavy nitrate concentration again leading to poisoning in fish.
Fish farming FAQ # 37: What are the common diseases in a fish?
The most common diseases found in fish are:
- Parasites of the mucous membrane and gill
- White spot disease
- Fin rot and mouth decay
- Fungal infections
- Fish tuberculosis
- Hole in the head disease
- Velvet disease
- Nitrite poisoning
Fish farming FAQ # 38: What diseases can one get from fish?
Some common diseases that can be transmitted to human beings from fish are:
- Fish TB
- VIBRIO infection
- Fish handler’s disease
- Mad fish disease
- Pfiesteria exposure causes skin sores, narcosis, red eyes, headaches, memory loss, nausea, liver or kidney dysfunction, blurred vision etc.
Fish farming FAQ # 39: What is latency period in fish?
It is described as the time interval between inducing the hormone into the female fish and the stripping of eggs.
Fish farming FAQ # 40: What is the minimum cost of fish feed?
The cost of feed depends on what type is being purchased. Fish feed may include pellets, rice bran, maize etc. commercial farms use a supplementary feed for their fish which could cost around Rs 35-50 per kg (average).
Fish farming FAQ # 41: What is the cost of fresh fish in the market?
Again, the cost depends on the type of fish, availability and its quality. The average price of fresh fish may range around Rs 150-550 per kg in the local market. The price may vary largely from location to location.
Fish farming FAQ # 42: What fishing equipments are needed for the fish farms?
The main equipments required for fish farming are:
- Hooks and line
Read: Tilapia Fish Farming.