Fungal diseases

This is also known as Cotton wool disease and the most common fungal disease is caused by the fungus Saprolegnia. In a healthy pond system, it is very rare, but can cause serious problems and death when the mucus coat of the fish is damaged due to jumping, flashing or other physical injuries. A Fungal infection is usually a secondary infection after a parasite invasion.

It often ruins a spawning as it attacks the dead eggs. Therefor it is extremely important to treat the eggs with Malachite green or Acriflavine and you should try to remove all dead eggs to prevent the fungus from spreading to the healthy eggs.

Fortunately it is quite visible as the mould/cotton wool like hairs develop. When this appears, immediate treatment must follow in failure whereof the infection might spread internally, and then it is often too late to treat effectively.

Treatment: Physically remove the growths with a cotton-wool bud dipped in Hydrogen peroxide. Thereafter, treat the area with undiluted Malachite green and cover it with Friars Balsam to seal the wound. Wait until it is touch dry and place the fish into your hospital tank. Hereafter, it is a good idea to treat your whole hospital tank with Malachite green. Methylene blue is also a good anti-fungal treatment.

Increase your salt levels in your pond and hospital tank to 3kg/1000 liters and monitor the wound every day, and should it not start to heal, repeat the abovementioned topical treatment.