Breeding commercial fish is one of the priority businesses worldwide. On private plots, carp and silver carp are often raised. However, by mastering specific techniques, you can grow more exotic commercial fish, such as the African catfish.
Species Description
The African marble catfish (Clarias gariepinus) is a typical representative of a diverse family of freshwater fish. In the wild, it is found in the non-saline waters of the Mediterranean basin, warm African lakes and floodplains, and the Jordan River.
This species has a large, flattened head with two pairs of long whiskers and a wide mouth equipped with sharp teeth. Its elongated body tapers towards the tail, and its shiny skin, often adorned with marble-like patterns, lacks scales. The color varies depending on the habitat and water conditions. The average lifespan is 8 years, with individuals growing up to 1.7 meters in length and weighing up to 60 kilograms.
During the African summer, rivers and lakes often dry up due to extreme heat. To survive, the fish has both gills and lungs, allowing it to breathe air for 12 to 40 hours while moving over land to find a new water source. In its native habitat, it quickly crawls across dry ground to locate suitable water bodies.
The African catfish is omnivorous, feeding on amphibians, mollusks, and small aquatic creatures. While it also consumes plant-based food, it behaves predominantly as a predator. In times of food scarcity, it may prey on weaker individuals of its own species. Additionally, it can generate small electrical discharges to ward off predators.
Housing Conditions
These resilient fish adapt to any water body, making them relatively easy to breed at home. They are tolerant of varying water quality and resistant to many diseases. A farm for African catfish can be established using a closed-loop water supply system, including the following components:
- Pond or tank: A minimum volume of 12 cubic meters and a depth of 1 meter is suitable for adult fish. The pond can be divided with nets to house fry and juveniles.
- Mechanical and biological filters: Settling tanks with aerobic bacteria help remove waste, ensuring a healthy environment. A reservoir for treated water is also essential.
- Pump system: Circulates water through the filtration system and back into the tank.
- Oxygenation system: Ensures sufficient oxygen levels in the water.
- Automatic feeder: Programs food distribution in precise quantities at specific intervals.
- Heating system: If breeding during cold months, maintain a water temperature of +20°C to +30°C. Proper heating equipment and insulated coverings are necessary.
While fish can also be raised in regular ponds, automated systems greatly improve health and yield. The species thrives in warm conditions, so outdoor farming without heating is limited to warmer seasons. Hobbyists have experimented with raising fish in large barrels or plastic tanks, but productivity is generally low in such setups.
Feeding Guidelines
Proper nutrition directly affects growth rates and immunity. Diets should be tailored to the age and size of the fish. Suitable food sources include:
- Commercial feed mixes;
- Animal offal;
- Fresh or frozen fish.
Feeding by age:
- Newly hatched fry feed on zooplankton for the first few days.
- At two weeks, they transition to paste-like feed.
- For fry weighing 100 mg, professional feed is introduced, and they are fed up to 10 times daily, with a total feed weight of 10% of their body weight.
- At 1 gram, minced spleen and commercial feed are added to their diet, and feedings are reduced to 8 times a day.
- By 1.5 months, weighing approximately 20 grams, they are fed 5 times daily.
Adult catfish (two years and older) are fed 2–3 times daily with a diet of fish by-products, defrosted fish, and trout feed. Each fish should consume about 4% of its body weight in food daily. It’s important to note that during food shortages, cannibalism may occur. Females require an enhanced diet during spawning.
Spawning Features
To form a broodstock, select healthy and robust females, providing them with optimal conditions and a special diet. The minimum water temperature for spawning is +18°C, with +26°C being optimal. Females seek quiet areas with dense vegetation to create nests.
Catfish spawn every 30 days, but professional farmers often stimulate this process using a single dose of a special preparation that encourages spawning. Nervous females may require sedation for egg collection.
Milt is collected from males and stored at +4°C for up to 24 hours. Eggs are divided into three parts, mixed with milt from three males, and gently stirred in water. After fertilization, the eggs are rinsed in a tannin solution (10 g of tannin per 10 liters of water).
Incubation occurs in frames or trays under controlled conditions (+24°C to +27°C). Fry hatch within 24 hours and are kept until their yolk sacs are fully absorbed. They are then transferred to separate enclosures.
African catfish can be successfully raised on both large farms and small private plots. By mastering feeding and care techniques, attentive farmers can achieve high yields with minimal expenses, producing delicious fish for personal use or sale.