Discus fish diseases
Discus fish diseases can be separated into external and internal.
External diseases usually are easy visible. If you see that your discus starts acting some like strangely or you see something like wounds or dots on your discus you can expect that your discus fish is sick.
The most common discus fish diseases are:
Aluminum Toxicity
Always remember to check your aquarium water pH (there are lot of good tests for checking). If pH rises above 8 or drops below 5 than your discus fish is in danger to get sick. Aluminum with these pH levels can be toxic to fishes. It can make a damage to your fishs breathing system. If you see some slimy material inside your discus gills you should check pH of your water and start the treatment.
Parasitic Anchor Worms
It is extremely rare parasite in our aquariums but sometimes they attack fishes. It can be brought by other sick fishes to your aquarium. If you want to avoid of these parasites than you should quarantine or disinfect you newly bought fishes. This should help. But if you see that something like a worm is on your fish and it is making a wound you can be almost sure that this is anchor worms. It is not very dangerous as itself but it makes wounds that can make you discus fish very sick because of bacterial attack. Potassium permanganate or salt dips should help treating your discus fish. Also there are some special cures in the shops that can heal your fish from parasites.
Fungal Infections
Fungal infections appear as white soft material on your discus fish skin. It is usually secondary infection because firstly parasites make wounds which are perfect place for fungus. Dips of salt and water cleaning should help you to cope with this disease.
Cloudy Eye Infection
Cloudy eye can be caused by eye injuries or parasites but mostly by poor quality water. To treat this you should make big changes of water - about 30% of water a day. Also try salt dips.
Columnaries Disease
Columnaris is bacteria that attack mostly weak fishes. If water condition in your aquarium is perfect than you shouldn't face with this disease. Columnaris disease is special because it can travel to another aquarium very easy - even through air. Columnaris disease can be spotted as white dots or scale margin of you discus fish. It spreads very quickly so you should start treating your discus fish as soon as possible, quarantine if needed. Keep the quality of aquarium water perfect and raise up temperature because bacteria don't like high temperature.
White Spot Infection
White Spot infection is caused by Ichthyophthirius Multifiliis parasite protozoan. This parasite attacks very fast and if untreated it lives in your aquarium till all your fishes are sick. It can be seen as white dots on your discus fish. Unfortunately many of fishes die after facing with this parasite. For treating you should go to a shop and buy some special cure. You have to use it every day because this parasite multiple very fast. Keep a temperature of your aquarium water lower. It will help to reduce the speed of parasite breeding.
Usually it is not easy enough to spot internal diseases because it is hardly visible. So better read this information below because if your discus fish will get sick you will easier spot it.
Headstanding or Loss of Balance
The main symptom of this disease is the loss of balance that makes your discus fish move strangely. It can be caused by poor water conditions, digestive system blockages, blood flagellates, swim bladder problem. First what you should do is to check your water's parameters. It is very likely that high ammonia or nitrite concentration can cause this illness. If this is the reason of disease than you should make a huge water changes. Generally treatment would be 1 tablespoon of salt to 1 gallon (4 liters) of water.
Dropsy and Popeye
Dropsy and Popeye are pretty common discus fish as well as other aquarium fish diseases. Usually it is caused by overeating or internal bacteria, parasites activity. If your discus fish doesn't eat properly or has swollen abdomen, blisters or bulging eyes, than you can think that your fish got these diseases. Treatment won't be easy. Firstly you should try Epsom salt - 1 or 2tablespoons of Epsom salt to 10 gallon (40 liters) of water. If this doesn't help than you should try antibiotics such as Kanacyn. Also don't remember to lower temperature of your water.
Fish Tuberculosis
This disease is caused by tuberculosis mycobacteria. Usually it attacks the discus fish when there are a poor conditions of water. Symptoms may include bloating, open skin sores, emaciation, strange swimming, loss of appetite, staying in a corner of the tank. Treatment usually ends in failure so better isolate your fish from others. Of course you can try adding some antibiotics or salt but there are not many chances that this will help.
Hexamitiasis
It is internal infection that is caused by protozoan. This Hexamita protozoan is not dangerous to many fishes but there are some groups of fishes for which it is dangerous. And one of them is discus fish. It is hard to recognize this disease but in early stage of it you can spot slimy whitish feces of your discus fish. Later your fish starts act strangely - likes keeping in the corner of the aquarium. You should treat this disease using Metronidazole. Be sure to treat your fish to the end because if your discus fish is not fully recovered than protozoan can attack your fish again and this time it can have resistance of Metronidazole.
Head and Lateral Line Erosion
This is chronicle disease and it won't kill your fish in one time. It can be spotted as skin de-pigmentation or occurring of small holes on your discus fish skin. Treatment is not very difficult - you should do water changes and use Metronidazole. That should help.
Tapeworm
Tapeworms are large worms that can parasitize inside your discus fish. It can be visible because it can stick out on you discus skin. The main disease is not tapeworms but bacteria and parasites that attacks your discus fish after tapeworms weakens it. Tapeworm disease should be treated using praziquantel.
