Black Ghost Knifefish

Question
Hi. We have a 42 gal. tank with some gourami and angel fish that get along pretty well. I added a Ghost about a month ago and he did well til about a week ago. He developed a fuzzy white growth/discharge out of his bum and started acting a little lethargic. What can I do? Please help. He is very cool and I would like to save him if I can. The water conditions have been good according to what I have researched(ph 6.5, temp 78, ammonia under control). The tank has been set up since Feb. Thanks  

Answer
Hi Andy;

It sounds like he may have injured himself and it became infected with a fungus. There is a fungus that causes cottony patches and lethargy called Saprolegnia. It infects wounded areas and sometimes the gills. Aquarium salt is very helpful but he will need an antifungal too. Go to your fish store and find a medicine that treats fungus. Look very carefully at the labels to be sure the remedy you use is safe for sensitive fish. Knifes are VERY sensitive. They don't have hard scales like other fish so they absorb chemicals more easily.

Medicines for fungus are mostly a green or blue dye. It is absorbed by the fungus and kills it. If you have a tank you can separate the fish to it would be better to treat that way. It is always best not to treat the main tank. These medicines will stain your aquarium sealant, plastic tubing and decorations. If you have live plants in there they will probably die. Also, your filter will remove some of the medicine and any fish waste in the established tank will absorb the medicine too and make it less effective on the sick fish. If you must treat him in the main tank, make a 25% water change and vacuum the gravel. It will help get rid of some of the stuff that affects the potency of the meds as well as helping to boost the fish's immune system.

A ten gallon "hospital tank" is very simple to set up and use. It only needs a heater, thermometer, air pump with air stone and a complete cover with lights. No gravel, no decorations and no filter. Fill it with 1/2 tank water from the main tank and 1/2 tap water. Use a water conditioner. Keep the lights off unless you need to view the fish for a few minutes and then shut them off. Fungus meds are light sensitive and knifes are nocturnal anyway. Make sure the temperature is the same as the main tank. Put the heater in and plug it in. Watch the hospital tank temperature very closely for the first few hours to be sure the new heater will keep the temperature at a safe level. You are going to have to use the hospital tank too soon to let it sit for a whole day like we would normally suggest for a new tank. After that looks okay, put the fish in after floating him in a bag of main tank water for ten minutes, just like you were bringing him home for the first time. You will need to make a 25% water change every 2 or 3 days.

Put the aquarium salt in a container of water to dissolve it. Dose at 1/2 teaspoon per gallon of tank water. Once the salt is dissolved in the container, pour it slowly into the tank. Don't add it to the filter or anything like that. (It will kill beneficial bacteria when the strong solution hits the filter and you don't want that.) Just slowly pour the salt solution right into the tank. Only dose the whole tank volume with salt once. When you make a water change in the tank, only treat the water replaced. In other words, if you replace 2 gallons of water, add back only a teaspoon of salt. Add the medicine and use it according to label instructions. If he is still eating, feed VERY lightly while he is sick.

Let me know if any of this is confusing to you. I gave you a lot of information so I realize you may need clarification.

I hope he feels better soon......

At Your Service;
Chris Robbins