Compiled by: Harun Kimani
Fish farming is an important component of Kenya’s agricultural sector, contributing significantly to food security, income generation, and employment. Effective management practices in fish farming ensure sustainable production, optimize growth rates, and reduce losses from diseases and environmental stresses. For agriculture and extension professionals, understanding the principles and practicalities of fish farm management is vital to support farmers, improve productivity, and promote best practices in the aquaculture industry.
Fish farm management practices are the organised activities and decisions through which a farmer keeps fish healthy, grows them to market size and keeps the farm profitable. They cover the water, the rearing units, the stock and the wastes the farm produces. In Kenya these practices must suit local conditions such as water supply, temperature and market demand, and extension officers help farmers to apply them. A farmer who stocks a pond and then does nothing but feed will see losses from poor water, disease and escapes, so management is a routine of checks and small jobs repeated through the production cycle.
Clear terms let farmers, workers and extension officers describe the same problem in the same words. The terms below are used throughout this unit.
Fish stock management is the planning and control of the number and size of fish in ponds, tanks or cages so that density, growth and health stay at a level the unit can support. Overstocking lowers water quality and raises the risk of disease, while understocking leaves the unit underused.
Stocking density is the number or weight of fish placed in a unit of water, for example fingerlings per square metre of pond. It is set from the size of the unit, the water supply and the species, and it is reduced when the water is poor.
A rearing unit is any structure that holds fish during production, such as an earthen pond, a concrete tank, a raceway or a cage. Each type has its own maintenance needs.
A feeding regimen is the schedule and amount of feed given to fish, set to meet their needs at each growth stage. A good regimen avoids waste, limits pollution and supports even growth.
Water quality management is the monitoring and control of physical, chemical and biological conditions such as temperature, dissolved oxygen, pH and ammonia, so that the water stays suitable for the fish.
Biosecurity is the set of measures that keeps disease-causing organisms out of the farm and stops them from spreading within it, for example controlled entry, clean equipment and quarantine for new stock.
Disease management covers the prevention, diagnosis and treatment of fish diseases so that deaths are kept low and the stock stays healthy. It relies on biosecurity, regular health checks and quick action when fish look unwell.
Waste management is the collection, treatment and safe disposal of the uneaten feed, faeces, silt, dead fish and other wastes produced on the farm.
Good management makes the difference between a farm that grows steadily and one that loses stock repeatedly. It ensures that inputs are used well, the fish stay healthy and the farm does not harm the environment around it.
Effective management ensures that fish receive adequate nutrition, live in suitable water and grow at the expected rate. This leads to higher yields and better quality fish for the market.
Regular monitoring and preventive measures reduce disease, and fewer fish die, which avoids losses of feed, labour and fingerlings.
Proper management reduces waste of feed, water and labour and lowers the cost of production. This matters most to small-scale farmers with limited capital.
By keeping water quality good and avoiding overstocking, management protects streams, wetlands and neighbouring land, and it helps the farm to meet the requirements of agencies such as the National Environment Management Authority (NEMA).
Well-managed farms produce healthy fish of uniform size that meet buyers' expectations, which strengthens their position in local and regional markets.
Fish management practices are the regular tasks that keep the production cycle on course. Each task is repeated at set intervals, and the farmer or a trained worker is responsible for carrying it out and recording the result.
Water quality is checked because fish cannot be seen to suffer until the problem is already serious. Readings are taken at the same place and time each day or week, usually early in the morning when oxygen is lowest, and they are written down so that a trend can be seen.
| Parameter | How it is measured | Guide for tilapia and catfish ponds |
|---|---|---|
| Temperature | Thermometer | About 25 to 30 °C for good growth |
| Dissolved oxygen | Oxygen meter or test kit | Above 5 mg/L preferred; fish are stressed when it drops low |
| pH | pH meter or test strip | About 6.5 to 8.5 |
| Ammonia | Test kit | As low as possible; it is toxic to fish |
| Water clarity | Secchi disc | A greenish pond showing the disc at about 30 to 40 cm |
Rearing units wear out and clog with silt, so they are inspected and repaired on a schedule. A leaking dyke or a blocked outlet can drain a pond overnight.
Prevention costs less than treatment, and the three threats are controlled together. Predators are kept out with the devices described under predator control devices in the chapter on constructing fish farming structures.
A fish farm produces wastes that, if released untreated, pollute streams and wells and harm neighbours. Good waste management also reduces problems on the farm itself.
Feeding is done by a trained worker on a fixed schedule, and the worker watches how the fish respond. Fish that rush to the feed and eat quickly are healthy, and slow or absent feeding is an early sign of poor water or disease. The farm records the amount of feed given and samples the fish at intervals to check their growth, which the farmer then uses to adjust the feeding rate. Recording of these results is covered in the topic Preparation of fish management records.
Create a free account to open more of this chapter.
Free: practical guides, quick cards, workplace scenarios and more.
Create a free accountThis chapter explored essential fish farm management practices, beginning with key definitions that clarify the terminology used in managing fish farms effectively. It emphasized the importance of addressing critical fish farm questions to ensure sustainable and productive operations. The discussion then focused on practical management assignments, including monitoring water quality parameters to maintain a healthy aquatic environment, routine maintenance of rearing units to support optimal fish growth, and strategies for controlling predators, parasites, and diseases that threaten fish health. Waste management practices were also examined as a vital component of maintaining farm hygiene and environmental balance. The chapter further detailed the preparation of fish management records, highlighting their role in tracking farm activities and making informed decisions. Finally, it covered the practical implementation of fish management procedures and the systematic documentation of these practices to support ongoing farm management and improvement.