Design by TargetWebsites - Last Updated 23rd April 2017

Conchak Investments Zambia

Fuel / Diesel

By definition, Aquaculture is the rearing of aquatic organisms in captivity.

An Aqua-culturist intervenes in the natural growth patterns of the organism that is being reared in captivity. This would include providing the best possible conditions for the maximum growth rate of the organism, providing the best possible diet, and interfering with the natural breeding habits. The global population increase has put the balance of nature at risk. The demands made on the natural resources, have started to exceed nature's ability to cope. This results in certain fish species dwindling or even becoming extinct. Aquaculture plays a vital role in re-establishing the balance of nature, by providing much needed food that has traditionally been gotten from natural resources, giving nature the chance to recover. There are many different ways of practicing Aquaculture; the environment dictates largely the ways and the species farmed. If there is ample water available, the fish may be kept in large floating cages. Artificial ponds may be built to rear fish or crustaceans.

The most intensive way of aquaculture would be the ’RAS', a closed recirculating system where the fish are farmed in large tanks, and the water filtered. The problem with Aquaculture in general is the need to maintain good water quality, for the fish to have the best possible conditions to grow. There is a need to filter out the solid waste, as well as the dissolved waste. Various types of mechanical filters can deal with the solids. The dissolved waste needs to be removed by biological means. There are also various types of ‘Bio filters', where bacteria are cultured that ‘digest' the harmful dissolved waste. Again there are a number of ways of dealing with that problem, but what all the solutions have in common is the need to effectively dispose of the effluent without having a negative impact on the surrounding environment. The best possible solution would be to make good use of the effluent. The effluent from Aquaculture is a source of very nutrient rich fertiliser for plants. Various systems have been developed to make the best possible use of those nutrients, effectively enhancing plant growth in agriculture, while solving the problem of dealing with the effluent generated by aquaculture. The simplest way would be to collect the accumulated waste and use it to fertigate pastures.


Types of Aquaculture

Cage Aquaculture

Only possible if large bodies of water are available.

Totally climate dependent.

Only suitable for endemic species

Vulnerable to predation.

Has environmental impact.

No control over water conditions.

Pond Aquaculture

The most commonly practised.

Climate dependent.

Only suitable for endemic species

Vulnerable to predation.

Has environmental impact.

Difficult to control water conditions.

Difficult to manage and harvest.

Needs access to Dam or River.

Relatively cheap to implement.

RAS Aquaculture.
Recirculating Aquaculture System

Total control over water quality

Total control over micro climate

Highest possible stocking density

Dependent on reliable power

No need to be near dam or river

Relatively low water consumption

Controlled effluent discharge

Suitable for alien species cultivation

Easy to harvest

Requires expertise to manage


The Hatchery is the most important and also technically most difficult part of any aquaculture operation,
irrespective of the type of system the fish will be reared in.
Without a hatchery to supply healthy and genetically diverse generations of fish, the whole operation is likely to fail.
The positive of this is that a single competent hatchery can support numerous aquaculture operations, and can also play a vital role in re-stocking presently depleted fish stocks in the wild.