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5 Common Tropical Fish Diseases

White Spot

White shop is a disease that most tropical fish keepers will encounter at some stage. White spot is a protozoan parasite which is extremely contagious and if left untreated deadly. Typical symptoms are sugar grain like spots on the fishes body and/or fins also the fish may be ‘flashing’ on the bottom in an attempt to scrape off the parasite.  Treatment is readily available and the whole tank must be treated even if only one fish is showing signs of the disease.

Dropsy

Dropsy is more of a symptom as opposed to a disease itself and can have many causes, many of which are untreatable. Symptoms include bloated body and protruding scales often referred to as looking like a pinecone. Some causes may be an internal tumour, bacterial infection of the scale pockets or internal bacterial infection. Although there many treatments on the market that claim to treat the disease successful treatment is rare, if the fish is showing signs of discomfort and pain you should consider euthanasia.   

Fin rot

Fin rot disease is a bacterial infection usually occurring in poorly maintained aquariums. Fin rot is caused by many bacteria that live in the aquarium if regular cleaning is not undertaken or the fish is living in poor water fin rot can occur. Symptoms include blood streaked and ragged fins, eventually the disease will eat away the whole fin. Treatment is readily available from most fish shop stores. 

Velvet

Velvet is similar in appearance to white spot however its appearance is more like a sprinkling of white/greyish flour as opposed to white spot’s sugar like grains. Velvet is usually caused be poor water quality (Ammonia, Nitrite or excessive Nitrate). Treatment is readily available and should be administered immediately.

Hole in the Head Diseases

Hole in the head disease is commonly seen on large cichlids such as Oscars but can affect all species, symptoms include pits or holes on and around the fishes head. Hole in the head disease is caused by the protozoan parasite Hexamita .The presence of this parasite on the fish is not usually enough to cause a outbreak of disease in the fish, poor diet and/or poor water quality are contributing factors. Treatment is available for this disease but often a change of diet and immediate improvement of water quality is enough to help.