DISEASES OF GOLDFISH
I have always thought that a clean, healthy tank is the best way to prevent diseases of goldfish. It is very rare for goldfish to get sick in well-managed tanks. The goldfish are happy and not under any stress. Stress is the biggest killer of goldfish as even if it doesn’t kill the goldfish outright, it can be a precursor of disease. Stress is caused by physical damage during transportation, lack of oxygen, wildly fluctuating temperature, overcrowding and introduction of new goldfish and/or disease. If you can avoid these you will go a long way to avoiding any problems.
Just like a stressed human, a stressed goldfish may look disheveled with a rough tail instead of rough hair. Although stress doesn’t kill immediately, we all know that continued stress will disrupt sleep, digestion, mood and eventually cause sickness. This may easily lead to death in goldfish.
Early diagnosis, treatment and isolation are very important tools in the battle against disease. The three causes of disease in goldfish are:
l. parasite infestation
2. bacterial infection
3. fungal infection
Each of these has many diseases in its sub-branches and many of them are always present in a tank. The goldfish only succumb under stressed conditions. It is just like us getting sick when we are run down. The immune system becomes weak and disease takes over.
My first step is to isolate the goldfish in a quarantine tank and check for problems. This will enable the other goldfish to have a better chance and also stop the sick goldfish being harassed. It can be a simple tank and it can also be used to check out new goldfish before they are added to your main tank. Fish can fast for a week without too many problems. If you think it may be a water quality problem stop the feed. Dirty water will kill them far quicker than no feed. Think also about what you have done to the goldfish recently. Have their been any dramatic changes? Consider all things. Especially check the filter is working.
Then check all the levels such as nitrate, ammonia and Ph are in acceptable limits. If still you cannot isolate the problem try a bit of non iodised salt in the water. This is a simple solution for parasite problems but a bit of salt in the tank will help the goldfish anyway. You can buy aquarium salt at most lish dealers. It can be introduced to the tank slowly at twenty-five grams for every five litres of water. This can be used over a period of a week by just changing some of the water each day to lower the salt level until it no longer exists. Another simple cure all is mercurochrome which can be used to disinfect damaged or infected areas on the surface of the fish.
There are many causes of goldfish deaths and unless you have a very special goldfish you wish to save it may be wise to accept some deaths from time to time. Goldfish that are in the late stages of sickness are rarely saved. The salt is the best and simplest remedy but you can purchase medicated feeds and move into the field of antibiotics. It is very hard to treat a goldfish, separate it and continue treatment without causing it some extra stress. Try to have the quarantine tank very similar in water quality to a healthy tank. If all your goldfish die suddenly go through the checklist of things to look for, drain the tank, leave it to dry in the sun and start all over again. Don’t put new goldfish into this tank without doing all this or else you will waste your money.
If you become very interested in goldfish pests and diseases there are some very comprehensive books available that will fill the big gaps in this information. Other goldfish owners are always happy to help you with any problems. As a final note you can take your fish to the vet but consider the cost of the fish to the cure. A dead fish will have to be autopsied quickly or frozen. I have never used a vet for fish.
For more detailed information on specific diseases please see the relevant section in tropical fish. This covers the common fish diseases in more detail and offers simple solutions to help manage your fish.