Above-ground catfish farming offers numerous advantages, including better control over production conditions. However, this type of farming is exposed to disease risks that can affect fish health and compromise your profitability. Early identification of these diseases, knowing how to treat them, and implementing preventive measures are essential to ensuring the success of your investment. In this article, we will review the most common diseases, their causes, symptoms, and the solutions to prevent and treat them.

Common Catfish Diseases

1. Fin Rot

• Symptoms: Discolouration and fraying of the fins, sometimes with reddish edges.
• Causes: Poor water quality, injuries, or stress. This disease is often caused by bacterial infections (Flavobacterium).
• Treatment: Apply antibiotic baths (for example, oxytetracycline) and improve water quality.
• Prevention: Maintain good pond hygiene, minimise stress, and ensure careful handling of fish.

2. Haemorrhagic Septicaemia

• Symptoms: Red lesions on the body, swollen abdomen, bleeding around the fins or eyes.
• Causes: Infections caused by bacteria such as Aeromonas hydrophila.
• Treatment: Administer antibiotics through feed after confirmation by a specialist.
• Prevention: Maintain good water quality, avoid overcrowding, and reduce stressful conditions.

3. Fungal Infections (Mycoses)

• Symptoms: White, grey, or cotton-like patches appearing on the skin or gills.
• Causes: Untreated injuries, poor water quality, or contamination by fungal spores.
• Treatment: Use antifungal baths with methylene blue or potassium permanganate.
• Prevention: Prevent injuries and maintain optimal oxygen and pH levels.

4. Parasitic Infestations

• Symptoms: Rubbing against tank walls, loss of protective mucus, and difficulty breathing.
• Causes: Parasites such as trematodes, protozoa, or flatworms.
• Treatment: Use antiparasitic treatments such as formalin or non-iodised salt.
• Prevention: Quarantine new fish and ensure effective water filtration.

5. Gill Disease

• Symptoms: Red, swollen, or mucus-covered gills, surface breathing.
• Causes: Gill parasites, poor water quality, or low oxygen levels.
• Treatment: Improve aeration and administer antiparasitic treatments if necessary.
• Prevention: Regularly monitor water parameters and reduce fish stocking density.

General Preventive Measures

Water Quality

• Monitor key parameters: pH (6.5–8), dissolved oxygen (at least 5 mg/L), and ammonia levels (kept as close to 0 as possible).
• Regularly replace part of the water to prevent waste accumulation.

Quality Feed

• Provide balanced feeds rich in essential nutrients.
• Avoid overfeeding, which can cause water pollution.

Regular Disinfection

• Clean ponds and equipment using safe products such as potassium permanganate.
• Ensure that any equipment introduced into the system is disinfected.

Fish Management

• Avoid overcrowding, which increases the risk of disease transmission.
• Handle fish carefully to reduce stress and injuries.

Quarantine

• Keep new fish in quarantine for 2 to 4 weeks before introducing them into the main pond.

Regular Monitoring

• Inspect fish daily to detect any signs of disease quickly.
• Keep a logbook to record observations and interventions performed.