Tropical Fish Diseases Diagnosing Tropical Fish Diseases Symptoms Tropical Fish Diseases

When our fish get sick, we often feel helpless. Helplessness is often accompanied by fear; fear because we can’t quite understand why the fish got ill and fear of losing our beloved pet. These fears can be alleviated with some understanding of what to look for in tropical fish diseases and how we can care for our fish during these difficult times.

Diagnosing tropical fish diseases is a difficult task even for the experienced aquarist. Some profession laboratories can perform sensitivity tests by taking a small sample of the fish to determine the proper antibiotic to administer. These tests are, however, quite expensive and not always conclusive.

There are many medications available depending on the symptoms your fish display. There are also a number of things you can do to care for your tropical fish during a period of illness. You can educate yourself on tropical fish diseases so that you are in a better position to identify the problem and get the appropriate treatment. Here are a few examples:

Fish Swimming in Circles

You may observe your fish swimming in circles with its fins clamped. This can be the result of some type of poisoning and will require you to check the contents of the tank to see if there are any contaminants, followed by a complete water change.

Sores or scabs

If there are ulcers on the body of the fish it could be the result of the Pseudomonas bacteria. This disease may also be accompanied by small haemorrhages from the mouth or internally.

Red patches on the body

These patches can be seen all over the body including the mouth and fins and are reddish in color. It is indicative of Fibrosis which is caused by the vibrato bacteria which spreads aggressively and can cause death. In addition to medication, a 50 percent water change is recommended

Bulging/cloudy eyes

Bulging eyes or cloudy eyes are two different symptoms associated with the same disease. There may be bulging in one or both eyes along with poor appetite, changes in the color of the fish and you may observe the fish attempting to hide. This could be Pistine tuberculosis requiring complete sanitization of the aquarium since there is no known effective treatment. Pistine tuberculosis can also appear in the form of cloudy eyes, one or both, with similar symptoms like appetite and color changes.

Clamped fins

The fish may appear to have their fins clamped to the sides and as such have difficulty swimming. This is a sign of chilling resulting from a drop in the tank temperature. Check to ensure the heater is working and connected. Under these conditions most of the fish could be affected but the problem could be resolved by restoring the proper temperature gradually.

While we can’t cover all the possible symptoms, it is important for the aquarist to check their fish daily in order to tackle any signs of illness expeditiously. Make note of the condition of the fish and the symptoms that you observe. For most of the diseases noted here, the treatment can be found at your aquarium supply store. It may be advisable to keep some common medications on hand just in case. There are a number of preventative measures that can be employed as follows;

Water testing

One of the biggest threats to fish is ammonia in the water; therefore, a test measuring kit is an essential item for any aquarium. Test kits are available for checking the phosphate, calcium and nitrate levels. Proper use of these kits, in addition to required medications and chemicals, will ensure your fish have a well balanced environment in which to grow and flourish.

Clean Tank and contents

Many potential diseases can be prevented by simple maintenance. Do not over fill your tank with gravel, a thin layer works just fine. Clean the gravel including, ornaments and props, and change some of the water regularly.

Changing water

If illness has been detected, depending on the gravity of the situation, you may be required to change some or all of the tank water, in some cases on a daily basis, until all signs of distress are no longer visible


Always have a supply of aquarium salt on hand and ollow the dosage instructions on the package. You can get natural aquarium salt derived from evaporated sea water and can be used to maintain the health of your tank. It acts to reduce stress on the fish, helps promote healthy gills and improves the efficiency of medications administered. Another must have is a Quick Cure package or similar product which can be used to treat a number of problems like spots, slime covered fish, and some fungi and parasites.

It is not realistic to think that all the fish in an aquarium will survive. But preventing and managing the diseases contracted by our fish, is essential to reducing loss. We can do so by educating ourselves on the kinds of diseases contracted by tropical fish, by maintaining a balanced eco-friendly environment, observing and understanding various symptoms of diseases and responding in a timely manner to protect our tropical fish.