The best way to deal with fish diseases is to prevent them from happening in the first place. If you don’t overcrowd, don’t overfeed, do partial water changes at least every 2 weeks and quarantine all new fish and plants then you will have avoided 90% of all fish problems.
In keeping with the KIS way of simplifying Aquarium Keeping, I normally use only 2 different medicines for treating fish illnesses. The first one is salt, regular table salt. Added to the water at about 1 teaspoon per gallon. This has been the miracle cure for me. Salt will kill or prevent most parasite problems, helps wounds heal faster and generally makes the fish feel better. The second miracle cure is copper. The easiest way to use it is to buy an aquarium medicine that contains copper in some form. My favorite is called Had-A-Snail. It was originally made to kill snails. In fact it kills all invertebrates, that includes snails, worms, shrimp, parasites, hydra and a host of other undesirables. Another product with copper in an usable form is Aquarisol. With copper the old saying “less is more” is a good rule to follow, you only use a few drops per gallon, so a little goes a long way.
Another very important cure for sick fish is CLEAN water. Polluted water is a big fish killer in tanks, and ponds and rivers. A water change can never hurt a sick fish and will usually help the situation a lot.
Here is a list of common symptoms, afflictions, their causes and cures.
Ich or ick or whitespot
Ick (Ich) or Whitespot
Look For: Tiny white spots on body, tiny black spots on body, clamped fins, bloody fins, gray or gold dusty patches on body, rapid moving of the gills and visible worms or fish lice on the body.
Causes: Parasites are usually introduced into the tank by new fish, plants or other decorations.
Prevention And Cure: All parasitic infections can be cured with the salt and copper treatments. Quarantining of new fish will prevent the spread of parasites. A mild half teaspoon per gallon addition of salt to the water will shield susceptible fish from parasites.
Fungus And Bacterial Infections
Look For: Cottony growths on the mouth or body of the fish. Infected wounds.
Causes: Usually a secondary infection stemming from a wound or polluted water.
Prevention And Cure: Clean water. Treatment with a mild salt solution for wounds will prevent infection. Maracin II will sometimes cure advanced stages of bacterial infections, but it will also kill your filtration bacteria, so you would need to carry out this treatment in a quarantine tank.
Severe Dropsy Infection
Look For: Drastically swollen body with raised scales giving the appearance of a pinecone
Causes: Usually a symptom of internal organ failure, maybe brought on by old age, poor water conditions or a combination of conditions.
Prevention And Cure: Clean water, proper feeding and the possible addition of a teaspoon of salt per gallon might help prevent this disease. In my experience the treatment for this disease is not effective, I advise quarantining the infected fish to prevent further infections to other fish and possibly euthanasia. Some people have reported successfully treating Dropsy with Maracin II .
medsWhen it comes to medicines for fish, it’s always best to use simple nondestructive cures like salt or maybe copper for extreme cases. The last thing a sick fish needs is to be living in a constantly changing chemical soup of fish medicines, pH altering additives and a dead bacterial filter bed.
Snails are not as big a problem as you may think, I like snails, only when they are severely overpopulating a tank are they really a nuisance.