Aquaculture and Fish Farming Products

The first question related to the construction of a pond refers to the size and number of ponds needed: If fish production will mainly only serve household needs and the fingerlings will be purchased from a hatchery, then only two ponds will be If a fish farming activity is intended that is independent of hatcheries,

Key requirements for growing fish in a pond Digging a hole in the ground, filling it with water and throwing some fish into it will not alone lead to success. To be successful, pond fish farming requires proper planning before starting. Land and labour – Before starting, the land and labour costs need to be

Proper integration of aquaculture into the farming system Proper integration of aquaculture into the farming systems is the primary aim in organic aquaculture in order to ensure sustainable production. Besides this, other aims of organic aquaculture include: producing fish with minimal negative effects on the environment; producing fish that contain as low as possible levels

Challenges to aquaculture in Africa Aquaculture or fish farming, in particular in Africa, is still facing several challenges, some of which include: Limited knowledge on fish farming – There is a general lack of adequately trained personnel to undertake aquaculture extension activities with farmers as well as limited access to good quality information. The few

Financial planning Starting an aquaculture business can be an expensive exercise. It is important that you first acknowledge that starting an aquaculture business is a big decision and requires serious commitment. Like any other business venture, some research needs to be done before money is invested. Depending on what you intend to use the fish

Important aspects in planning an aquaculture business   Skills: Aquaculture, like agriculture, requires knowledge of the biology of the species cultured. A project started by unskilled or untrained staff is unlikely to have any chance of Formal organization: Any business needs formal organization and division of Some people have technical skills, others know office or

Basics of business planning: key questions Aquaculture is no different from agriculture when considering whether or not a proposed venture is worth doing. Just as a farmer is not going to buy cattle if grazing is unavailable, nor plant crops if suitable arable land is not available, nor should he/she consider aquaculture if sufficient water

Q: How can production be increased in ponds? A: In general, production is increased by improving water quality, so that fish can be held more intensively, and by increasing food quality and quantity. This has to be balanced against input and running costs such that the venture is not over-capitalized in terms of expensive technology.

Irrigation of farmlands and fish farming If the ponds are built so that the water level is higher than the crop fields, it is possible to drain the water to irrigate the farmlands. This has a number of benefits. First, the water is reused, which is important in southern Africa due to the limited supply

Polyculture Polyculture is culturing two different species at the same time. The two species use the same space but because they have different habits and diets, they do not negatively affect each other. In many cases the growth of the different fish is better than when they are grown alone in the same pond. This

Monoculture The most commonly farmed fish in Africa is tilapia. The most frequently used species is Oreochromis niloticus stocked at 1-2 fingerlings per m2, with an average stocking size of 5-10 g each. The ponds are fertilized with manure or compost and the fish are fed irregularly using locally available ingredients. The production cycle lasts

Increasing the production from ponds To increase the production of a pond, a fish farmer has a number of options available. These include combining different species of fish (polyculture) or growing fish along with other domestic animals (integrated aquaculture).

Q: What are the disadvantages of cages? A: The set-up  costs can be high initially; these include the costs of building large robust cages  that can withstand rough weather. Cage culture can be prone to damage and there is a risk of escape of the entire stock should the cage break or be damaged by

Q: What species of fish are suitable for cage culture? A: Species that grow well on artificial manmade diets are some of the best candidates for cage culture. This is because many of the health and growth requirements of the fish have been experimentally determined and the feed formulation can be optimized for variable conditions.

Q: When/why should cage culture be considered? A: Cage culture is an alternative to building containments for fish aquaculture (ponds, tanks, etc.). Pre-existing water bodies such as dams, lakes, estuaries or the sea are used for cage culture. This means that no capital is required for additional building containment (such as plumbing or filtration) other

Types of cages Small cages Most people assume that fish cages are all very large and expensive. This is not true. In the Far East, many ornamental fish are cultured in small   mesh cages called pen-nets or ‘hapas’ which are often set together in groups in fertilized ponds or small dams. Pen-nets are staked

The advantages of fish cages Cages are less expensive than building ponds, dams and other Cages can make use of existing water bodies (such as lakes, dams or the sea) that have good water quality. Cages do not require land-ownership and can be moved to the most suitable Cages protect fish from predators and Cages

Cage culture of fish Cages are widely used around the world to culture fish in natural or artificial water bodies. The use of cages in aquaculture has several advantages which are summarized below. Cages have some disadvantages, such as not allowing the fish access to the substratum from which they can feed or seek refuge,

Q: How many fingerlings can I get from one spawning? A: A mouth-brooding O. mossambicus of around 500 g may spawn up to 500 eggs, a substrate- spawning Tilapia rendalli may produce up to 3000 fry. Barbel and carp can produce several hundred thousand fry per spawning from a 3-4 kg female. Trout may produce

Q: Will trout breed naturally in dams or tanks? A: No, in South Africa, only rare wild populations of trout, in certain rivers where environmental conditions are perfect, breed naturally. Most farmed trout are stripped and then artificially reared from the fertilized egg stage.

Q: Will barbel (C. gariepinus) breed naturally in ponds, and will I get lots of fingerlings from them? A: Barbel will sometimes spawn wild in ponds, but production will be very low and most will be lost to predators and cannibalism. Cultured barbel need to be spawned artificially.

Tilapia (Oreochromis mossambicus) One of the inherent disadvantages of tilapia as an aquaculture species is its tendency to breed at an early age and small size, and thus overpopulate ponds with small fish. However, the availability and quality of tilapia fingerlings achieve this, tilapia can be bred during winter in indoor tunnel-covered tanks where the

Maintenance of fish broodstock One of the essentials of good animal husbandry is the high-quality care taken of broodstock year round. Emaciated or diseased stock can hardly be expected to perform well when called upon to breed, so the conditions under which breeder fish are kept is paramount to their performance. Generally, with the exception

Q: How can I prevent disease from spreading from pond to pond? A: If fish in a particular pond or cage are infected do not use any equipment such as nets or buckets from the infected pond or cage in the other ponds or cages. Try to sterilize all such equipment in acriflavine or permanganate

Q: What do I do when the fish stay on the bottom with clamped fins, are skittish, and refuse feed? A:    This is usually a sign of high ammonia content. Do a water test to confirm this (anything over 0.1 ppm ammonia is high and can be lethal to some species). Carry out a water

Q: What do I do when all the fish are seen gasping at the surface? A: This is usually a sign of low oxygen content, often seen early in the morning. The water quality is probably low, or the fish containment overstocked. Carry out a partial water change and reduce the stocking load immediately, and

Q: What do I do when the fish seem to be sick? A: The golden rule is to cease feeding as most diseases are a result of poor water quality made worse by excessive feeding, resulting in uneaten feed breaking down into toxic ammonia. Increasing the water flow to dilute toxins or poor water quality

Q: What medicines should be kept on a fish farm? A: In reality very few. Disinfectants such as acriflavine, permanganante of potash or formalin are valuable for sterilizing tanks. Salt is a useful and benign substance that can reduce stress in fish under certain circumstances. Malachite green or methyllene blue crystals are useful in eradicating

Q: How long does harvesting take? A: Always longer than you think! Even the draining of a small 0.25-ha pond can take several hours. It is advisable to start draining the pond beforehand to allow more time to catch, clean, and package the fish the following day, and to get them to market that same

Q: What size should fish be harvested at? A: This aspect depends on the market that you have targeted in your operational plan. If the market is prepared to accept smaller fish, this will make harvesting and handling easier. Rural markets tend to accept fish at smaller sizes (150-300 g) while urban markets often prefer

Q: What aspect is most important to prepare before the actual harvesting of fish? A: It is important to be mindful of the harvested fish as a product and to remember its market value when preparing for this stage of the operation. You must be organized as to what is going to happen with the

Managing fish health and diseases Under culture conditions fish are more likely to encounter disease as many fish are kept close together, sometimes under stressful conditions. It is therefore very important that farmers carefully watch their fish for any strange behaviour. If disease is detected early it can be treated accordingly; disease treated too late

Smoking fish Smoked fish do not last as long as salted fish. This is because they need to be refrigerated, frozen, or canned if they are to be kept for long periods. A smokehouse is used to make smoked fish. A simple smokehouse is a shed or box built over a (controlled) fire so that

Preserving methods Salting fish Salting is one of the oldest methods of preserving fish. Salting allows a farmer to keep fish for long periods so that they can be used when fresh fish are not available. Salting depends on the species, the size of the fish, and on the amount and quality of the salt

Harvesting from tanks or cages Catching fish from either tanks or cages is somewhat easier than from large earth ponds. Tanks are drainable and the fish can therefore be caught progressively as the water drops, as opposed to all-at-once in a large seine net. However, the quantity of fish held in large tanks or cages

Q: When do fish first need feeding? A: In artificial containments such as tanks, raceways or cages there is no or very little natural food, so all the fish’s diet must come from artificial feeds. Fry born into this near sterile environment will need feed as soon as their yolk sac is used up (typically

Once the pond is full of water there are a few things that need to be done to ensure that the fish will have a place where they will be unstressed and will grow well. Making sure that there is an abundance of suitable food in the water is an important aspect. With tilapia, carp

Q: Do I still have to artificially feed the fish if the pond is fertilized with compost or manure? A: To obtain maximum production, yes. Fertilizing a pond may increase production by 30-40% over non-fertilized ponds, but feeding the fish an artificial diet will further increase production by another 30-40% or more. However, if feed

Tanks are generally smaller than ponds and are constructed above the ground. They are not in contact with the soil and tend to have a solid base (usually concrete) making them usable both indoors and outdoors. Tanks vary in size and shape depending on their use (e.g. culturing phytoplankton or larval fish) and can range

Size grading should be performed often to remove stunted individuals. Sex-sorting should be done when the fish start maturing in order to prevent uncontrolled spawnings which not only reduce the quality of the fish (due to inbreeding) but also slow down the growth rate (as the fish put energy into reproduction rather than growth).   In

Juveniles will feed on an artificial diet (33-35% protein) or homemade diets using fishmeal, beef heart, and liver. The fish will also feed on the natural zooplankton in the pond. Adults are fed a formulated diet or flake at a ration of 3-10%, depending on size and species. The food should contain pigments to enhance

The males and females are placed in a fish tank where they mate. As their name suggests, livebearers give birth to live young, which means no problems with trying to incubate eggs. As the young are born they are able to swim, feed and fend for themselves. However, if there is nowhere for the babies

Trout eggs are relatively large compared to most other fish eggs. After the fry have hatched and used up their egg sac, they can be fed on  an artificial diet. The fry are usually reared in circular fibre-glass or concrete tanks to maintain a regular current and uniform distribution of the fry. Water is sprayed

In the wild, trout feed on aquatic and terrestrial insects, molluscs, crustaceans, fish eggs and other small fishes. The natural diet is rich in pigment and this is responsible for the orange- pink colour in the flesh. In aquaculture, the addition of pigments in the fish food causes this pink colouration.   Trout feeds have

The most suitable ponds for growing out juvenile carp should be shallow, weed-free and drainable (about 0.5 to 1.0 ha in size). The nursery ponds should be prepared prior to stocking to encourage the development of a rotifer population as this provides the fry with their first food. The ponds should be inoculated with other

Carp mature after three years and in the wild, and spawn every year in the spring, releasing up to 100 000 eggs per kg of fish body weight. In captivity, male and female fish are placed in spawning ponds or tanks during the spawning season. To make the captive broodstock breed, fish can be injected

Sharptooth catfish (Clarias gariepinus) The sharptooth catfish or barbel is a freshwater species and is distributed throughout southern Africa. This is a warmwater species that prefers temperatures between 20-30˚C. Unlike most other fish, catfish do not have scales but rather a naked skin; this makes handling them easier as scales are not lost causing damage

Q:   How many eggs do fish produce, and how often do they breed? A: This varies greatly between species. Carp and catfish may breed once a year and produce in excess of 100 000 tiny eggs per female. Tilapia may breed three to four times each summer and may produce 500-1000 eggs per spawning. Guppies

Q: How do fish feel their environment? A: Fish have a sensory organ called the lateral line which lies along the mid flanks of the fish. This organ is very sensitive and can pick up vibrations in the water, warning the fish of other species or predators in the water or on the bank. Using

Q: Can fish see colour, and do they have good eyesight? A: Yes, many fish have excellent eyesight and can see a wide variety of colours very efficiently. Many fish, like tilapia, recognize their mates by colour differences during the breeding season. Some species, such as the catfish Clarias gariepinus, have small eyes and poor

Q: How does a fish swim? A: A fish swims by contracting its lateral (side) muscles and then flexing the body muscles along its length, which basically pushes the water behind the animal. Fins are mainly used for directional stability. A fish can only move its body one way, so when you see a fish

Q: Since a fish is surrounded by water, how does it protect itself from water-borne diseases and parasites? A: A fish has an immune system, just like any other animal, that if healthy, will protect it from most diseases. Fish also have either scales or a mucus coating (or both) that protects them it from

Q: Why are fish more efficient at converting feed into mass than land animals? A: Fish need food only for movement, not for staying warm or for ‘fighting’ gravity. For example: a fish can move upwards in the water for 100 m for the same energy that it takes to horizontally move 100 m at

A spirit of hard work coupled with preparedness to undertake more than just fish farming itself.  If you are going to call a mechanic every time your vehicle needs an oil change, or      an electrician when you need to wire up a pump, rather go and become a desk-bound civil servant, as fish farming demands

The choice of what species should be cultured  in a particular region depends on a number of factors, as discussed below. Location Several introduced (exotic) species have caused or threaten conservation problems to indigenous species due to their hybridisation, the introduction of parasites, or by out- competing naturally occurring species for food or other resources.

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

It is important to know Aquaculture Farming Nutrition At Southern Africa Youth Academy we provide training Aquaculture and Fish Farming Nutrition. We know and understand how painful it can be to see your water dirty because of over feeding and fishes not eating the food you are giving to them. To register for our Aquaculture

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

To partner with Southern Africa Youth Project Please send an email to info@southernafricayouth.org or call us at + 27 11 071 1903 Distance or online courses and qualifications click here To apply for jobs click here Make a donation now click here Partner, fund and give a grant click here Company Registration Services click here

Here we shall the list of all the Aquaculture and fish Farming Products you need. At Southern Africa Youth Business we list all the Fish Farming products that you needs to ensure your farm runs smooth. Let us get into it: Water Pump Water Filter UV Light Filter Sand Bricks Cement 32.5 or 42.5 Pond

Q:    Is a filtration system necessary? A:    Extensive or semi-intensive earth ponds are generally unfiltered. Many raceway systems are flow-through with no filter. Where water volume is limited, or the fish are cultured intensively, a filter becomes vital to maintain water quality. Fish cannot be grown in small tanks (<5000 l) of stagnant water without

The design and construction of ponds is very important if a fish farm is to operate properly. Ponds are earthen impoundments for holding aquatic species and have been used for thousands of years. Ponds can be holes in the ground (sunken pond), a dammed-off valley or stream bed (barrage pond), or constructed above ground (embankment

Temperature is the hotness or coldness of something and is probably the most important water-quality variable. Unlike mammals, fish are not able to regulate their own body temperature and therefore have a body temperature similar to that of the water around them. Therefore, all fish have a minimum and maximum lethal temperature limit. Temperature affects

Harvesting from ponds If the pond can be drained, harvest the fish by draining the pond into the catch basin and collecting the fish with a scoop net. If the pond cannot be drained, drain out as much water as possible and use seine nets to catch the fish. It must be remembered that, in

The care of the cultured fish (fish husbandry) is one of the most basic aspects of fish farming, yet one which is often almost ignored in many manuals on fish farming. In all aspects of their lives, fish need to be maintained in conditions that allow them to thrive and grow, or to reproduce well.

Packing un-purged fish taken from a dam or pond It is unwise to pack fish that have been caught from ponds or tanks where they have recently eaten. This is because they have a gut full of food that will be expelled in the packing water, thus polluting it. Tilapia are especially difficult in this

Q:    Is it possible to over-fertilize a pond? A:    Yes, if too much is added the pond water becomes anoxic (lacking in oxygen) and the fish will die.

Let’s Start by building the Pond for your fish farming At Southern Africa Youth Business we travel around the world building fish ponds for commercial and residential use. whether you are looking to build a pond for residential or commercial use. our work includes: Site Audit: We will check the location where you are based.

Appropriate stocking of the pond   Depending on the available feeding resources, 2 to 4 fish per m² of pond area are appropriate with a sex ratio of one male per 4 to 5 females. The male fish should weigh 200 to 300 grams, the females 700 grams or more. In most Orechromis species, the

Fish breed in a number of different ways. Most lay eggs but some give birth to live young. In freshwater fish, the fertilized eggs usually sink to the bottom or are sticky and therefore stick to plants or rocks. In some species (such as tilapia) the eggs may be collected by the adult fish and

Predators such as birds, frogs, otters, snakes and lizards may eat many small fish, thereby reducing the number of fish available at harvest. If predators are found in the pond they should be removed and released far away from it. Fences may need to be installed around the edge of the ponds to prevent predators

The type of soil available to construct the pond is of the utmost importance if the pond is to hold water, maintain water quality and not fall apart. The soil properties that must be considered for pond construction include:   Physical – The texture, strength, stability and water-holding ability (such as clay) of the Biological

Water availability and quality There must be sufficient water available to ensure the ponds are always full when holding fish. If water is only available for part of the year, production should be restricted to fall within the same period. As the fish grow they will require more food and in turn will produce more waste.

Q: What is the potential for other species? A: Any fish species not indigenous or present in this country has to pass a ‘conservation risk assessment’ with the various nature conservation departments. The protocols for this have not yet been worked out; therefore, it is unlikely that other exotic species have realistic potential at this

Q: How can I get into ornamental fish culture? A: It is the marketing that has to be well-organised and the cooperative approach works best. Ornamental aquaculture is well-suited to the concept of ‘aquaculture zones’ where numerous small-scale fish farmers pool their resources and market their product collectively to a central buyer who will help

Q: Are barbel Clarias gariepinus really an attractive aquaculture species? A: Yes, and no. They have good culture potential in that the techniques have been well documented, but market acceptance still remains a challenge. Be cautious of this species at present until potential markets become more reliable.

Q: Where can I grow trout in South Africa? A: Trout need abundant cool running water to thrive, thus the higher, well-water regions of the Mpumalanga escarpment, KwaZulu-Natal Drakensberg mountains, Eastern Cape Amatola and Drakensberg highlands, and the upland regions of the Western Cape are the best regions for trout. Other more localized regions suitable

Q: Can I grow tilapia on the Highveld? A: In summer all parts of South Africa are suitable for growing tilapia if the water is over 20˚C. However, winter water temperatures that fall below 13˚C will kill farmed tilapia, and they will not grow well at temperatures below 18˚C. Thus, only a summer ‘crop’ can

Q: Is ornamental fish culture highly specialized and complicated? A: No, if this was the case how is it that in the far East thousands of rural farmers make a living from it? Ornamental fish culture can be done in simple small earth ponds, in the warmer parts of the country. Coldwater ornamental fish (goldfish

Trout is the most well-established aquaculture species in South Africa. It is very popular as a fishing species as well as a high-value food fish. Trout is not native to South Africa and was introduced over 100 years ago by people who wanted to catch them on a rod and line. Since then they have become established

Advantages and disadvantages of tilapia (O. mossambicus) as a candidate species:  Advantages                                                              Feed at a low trophic level (they can eat a wide variety of

Q: Is aquaculture a fulltime occupation or an alternative to other farming practices? A: It can be either, depending on its scale. Some fish farmers are also crop or other livestock farmers, while others are fully occupied managing their fish farms which leaves no time for other occupations.

Q: Can a farmer use his dam or water-storage tanks for aquaculture? A: Generally, no, in that these tend to be either unmanageable because they cannot be drained and the stock managed, or too small in that the feed needed to grow a worthwhile number of fish would soon pollute the small water volume of

Other carp species Other kinds of carp, besides the common carp, are grown in ponds. Most commonly used are the Chinese carps. Some of these are –   Silver carp (Hypophthalmichthys molitrix). This fish eats phytoplankton, but will accept rice bran and bread crumbs. The silver carp gets its name from its silver It has

Good water quality is essential to the health of fish at all stages of development. Water- quality requirements differ between species and between the different life stages as the fish develop. Many of the water-quality parameters are interlinked and a change in one feature can have an effect on another. Therefore, it is important to

Q:    Is predator protection vital or a luxury? A:    It is essential to have protection against animal predators as they can reduce stocks to almost nil if allowed unlimited access to the ponds or tanks. Fish farms in areas near human habitation also need protection against theft of the stock (fencing and alarms) if the

Q: Does one need lots of water for fish farming? A: No, the Israelis (for example) farm fish in one of the driest parts of the world. The quantity of water available determines the methods used, whereby intensive water recirculating methods tend to predominate where water is scarce, and extensive ones where water is abundant.

Q:    Can I do aquaculture in a farm dam? A:    Not unless the dam can be drained and managed like a farm pond. However, you can utilize a dam for cage-culture.

Q: Do you need a university degree in zoology or ichthyology to become a successful fish farmer? A: No, a good practical ability is more important, although a basic understanding of and ‘feel’ for animal husbandry is essential. If you have no ‘feel’ for animals, do not become a fish farmer.

Q: Do fish get sick like land animals? A: Yes, all animals get sick, but fish usually only get sick in large numbers when their environmental conditions are not to their liking, such as the result of polluted water or temperature stress. Because fish are so dependant on their environment, being cold-blooded, diseases are very

Q: Is fish farming profitable? A: Fish farming is a business just like any other,  and the growing of the fish is only one aspect,  just like the growing of crops is only one aspect of traditional farming. The farmer also needs to be competent at harvesting, processing and selling the harvest, and in running

The practice of aquaculture varies widely and differs in the intensity of culture, level of water exchange and structures used, with each method having its own set of benefits and problems. Aquaculture can be broadly grouped into three intensities: Extensive – This uses large stagnant ponds that allow only a low stocking density and rely

During the late 1960s and 1970s various government agencies promoted freshwater aquaculture. Well-equipped hatcheries were constructed in many parts of the country to supply fingerlings to both private and government projects. Of the 13 government hatcheries then existing, the three remaining are operating at reduced capacity and efficiency. Most of the hatcheries and rural projects

Q:    Can I grow fish in a concrete or plastic water-storage tank? A:    Not economically; fish tanks are best purpose-built, as they must be shallow, drainable, have clean water (preferably filtered) and be large enough to produce economically viable quantities of fish. One tank does not make a fish farm!

Q: How do I know that the fish are profiting from eating an artificial pelleted ration? A: As the fish grow you will need to take regular samples from the pond, tank or cage, to assess the growth rate. These growth figures can then be compared to available growth patterns for unfed fish under similar

Harvesting and preserving fish Harvesting is the collection of fish from a pond, for selling at market or for cooking and preservation for family use. Harvesting can refer to collecting all the fish or to taking out only some of the fish (this happens often in tilapia ponds which have both young and adult fish).

Q: Do I need to feed my fish fry with expensive, carefully formulated fry diets? A: No, in general most fry and fingerlings can be reared quite successfully on ordinary crumbles and small pellets, if specifically designed for trout, carp or catfish, combined with some natural foods where possible (like green water full of phytoplankton).

Q: Are all dry fish pellets equal in terms of quality and palatability to the fish? A: No, definitely not; there are some very poor-quality feeds available that have very little food value at all, so only purchase from a recommended source. Some of these feeds clearly taste unpleasant to the fish too, and so

Q: How do I know that the fish are eating the expensive feed I am throwing in? A: Always feed the fish at the same time and place each day: fish soon become used to this and you should be able to see the increased activity in the water when fish are feeding. To check,

Q: Can I feed the fish with kitchen waste? A: Yes, most tilapia, carp and catfish will readily consume kitchen waste, especially vegetable, meat and grain waste. If introduced in reasonable quantities, what is not immediately eaten will break down to fertilize the pond. Fish reared in tanks or raceways are not usually fed such

Q: How much should fish be fed? A: Artificial feeds deteriorate very quickly in water, so any feeds not eaten immediately will quickly spoil and become little more than expensive pond ‘fertilizer’. The general rule is to feed what the fish will consume in five minutes.

Q: How often do fish need feeding? A: Juvenile fish should ideally be fed three or more times per day, but in reality this is often impossible to do; so two feedings per day is the norm, with one per day for sub-adult fish.

As each species eats a different diet, each species of fish has its own nutritional requirements. Carnivorous fish (such as catfish and trout) require a high protein diet (around 40%) which has a high proportion of fishmeal. Herbivorous species require a lower protein content (around 30%) and can be fed a higher proportion of plant

Q: How long will fish survive in a bucket? A: Fingerling-sized fish of 4-6 cm will survive at a stocking density of 20-30 fish in a 10 l bucket  for 20-30 minutes; 100 such fish will only last 5-10 minutes before they start gasping at the surface.

Q: How many adult-sized fish can I pack in a drum? A: You can pack about 20 purged adult tilapia of 500-550 g (or 20 x 250 g trout) in a 200 l drum with a blower bubbling air through an airstone in it, for a journey of around 4-6 hours, and expect them to

Feeding habits It is important to know the feeding preferences of the species being cultured so the correct food can be provided at all times in order to maximize growth. The feeding preferences are determined by observing the fish as well as by examining the gut of naturally occurring fish. Fish (and other animals) can

Q: How many fingerlings can I pack in a plastic bag? A: You should be able to pack 100 x 4 cm purged tilapia fingerlings in 3-4 l of water in an oxygenated double plastic bag, and expect them to survive well for up to 12 hours.

Fish (and other animals) require food to supply energy for movement and other activities as well as for growth. As fish are ‘cold-blooded’, their body temperature is the same as the water in which they are living. They therefore do not have to use energy to maintain a stabile body temperature and therefore tend to

Why feed the cultured fish? A fish farmer may wonder why he needs to add extra feed to his pond when he already adds fertilizer to provide food for the fish. Since food is expensive, the farmer may not be willing to provide the fish with extra food and must therefore be taught why additional

Size-sorting the fish After the fish have been collected in buckets, they should be sorted by sizes or species. If sorting is done quickly, small fish can be returned to the pond to allow them to grow further. If size-sorting is needed, it is recommended that one or more portable fish pools be erected in a

Packing small fish or fingerlings Small fish the size of fingerlings (3-8 cm) can be packed in double plastic bags which are then placed in boxes for transport. Packing water must be prepared in advance and should be absolutely clean and of the same temperature and quality as what the fish are used to. Never

Long distances A particular procedure is required when moving fish over longer distances, such as when stocking ponds with fingerlings or obtaining broodstock. These fish should never be fed for at least 24 hours (preferably 48 hours with tilapia, due to their long gut length) before transporting them as they will foul the packing water

Short distances When moving fish short distances within the hatchery itself, they can be transported in buckets. Remember that certain fish almost invariably try to leap out of buckets (Tilapia rendalli and catfish) so the buckets need lids or netting covers. Fish that leap out of buckets and fall into dust or earth lose their

Like fertilizers with nitrates, chemicals used by farmers to treat plants against pests may find their way into the water. Care must be taken to ensure that the water running off land farms near to aquaculture farms doesn’t have pesticides. Even low levels of pesticides are toxic to fish and many of the other pond

Packing large fish For large fish over 10-12 cm, plastic bags puncture too easily and other containers are used. The best are the blue or green plastic 50-200 l drums with an open top that can be clamped on. For short time intervals (<15 minutes) large fish can be moved around the farm in these

Phosphorus is necessary for the pond organisms to survive and is often important in the regulation of algal growth and subsequent food webs in the pond. The level of phosphorus in ponds is usually around 0.05 mg/l. If a large amount of phosphorus is added in the form of fertilizers, sudden algal and plant blooms

Tank and cage management Tanks, raceways and cages are all artificial enclosures that need daily management to work efficiently. The life of the fish contained in these structures is entirely dependent on the lifesupport systems installed (pumps, blowers, water flow and climate control in the case of tanks and raceways; feeding and water quality in

Transporting live fish One of the most frequent activities on any fish farm is the moving of fish around from one tank to another, or from pond to pond, or even the collection of broodstock from elsewhere. Sorting stock, stocking grow-out tanks, moving broodstock, harvesting fingerlings, sampling growth rates, and catching adult fish for selling

Fertilizers To ensure pond phytoplankton productivity, various nutrients such as nitrogen, phosphorus, potassium, carbon and calcium need to be added regularly. Fertilizers can be inorganic fertilizers or mineral fertilizers, or else organic fertilizers or manures of plant and animal origin. Organic fertilizers Organic manures have been used for a long time. They can be obtained

Ammonia is probably the next most important water-quality factor after dissolved oxygen. Ammonia comes from decomposing material, such as plants and dead fish. It also comes from the fish as part of their normal metabolism and is excreted through the gills. If large numbers of fish are kept together the levels of ammonia can quickly

Like humans, fish also use oxygen; however, the oxygen available to them is that which is dissolved in the water and is measured in mg per liter. Naturally, oxygen enters the water through the surface of the water and the amount that is capable of entering the water can also be expressed as the percentage

Minimizing feeding costs   The feed is one of the most important factors influencing the growth and health of the fish. Minimizing feeding costs is thus of great interest while ensuring sufficient good quality feed to ensure appropriate growth and good health of the fish. Tilapias can basically be fed by fertilizing the pond with

Feeding the fish through the integration of plant production Alternatively, to or in addition to adding manure to the pond, materials of plant origin can be used to feed the fish on a low production intensity level. Farm-own vegetal feeds include leftovers from fruits such as papaya or mango. Leaves and other vegetal material are

Floating and sinking feeds