sick cory catfish

Question
hello - my friend WAY overfed my fish while I was on 2 week vacation. I have a 5 gallon with a neon tetra, a male guppy and a cory catfish. My guppy died while I was on vacation. I removed my remaining 2 fish, drained the tank and cleaned everything (even the gravel), replaced the filter and water and returned my fish (this took about an hour). My tetra is fine, but my catfish became ill 4 days after the water change & cleaning; up until then he was very perky. He tries to eat but keeps floating around, e.g. he cannot stayed anchored. I do not see any signs of parasites or fungus or spots on his body. Does it sound like swim bladder disease? Can I do anything for him? Is it possible shock from the complete water change? I have had him for 6 months & he was very tiny when I got him - what is their usual lifespan? On a separate note - a while ago I got a very small algae eater because I had a lot of brown algae in my tank. Over time he ate all the algae, then suddenly died. I'm guessing he may have run out of food. Is there any food supplements that you can give them that they will eat? Thanks you for your assistance.

Answer
Hi Nancy;

What a tough time you and your fish have had! What a shame.

It is possible the cory cat is experiencing the effects of "New Tank Syndrome" after the bacteria balance was disturbed in the cleaning. If it has been a week or so that's probably it. It takes that long for toxins to build up. With the bacteria reduced or killed, ammonia and/or nitrites build up and the fish can get sick. Often, bottom feeding fish are the first to suffer it's effects because that's where the waste is that makes ammonia and is also where the bacteria lives to turn that ammonia into nitrite.

If it has only been a couple of days it may just have been the stress of the cleaning and excess food and maybe he even ate some spoiled food that poisoned him. Hard to say for sure.

Either way, make another partial water change. Maybe replace 25% every day for the next 4 days to reduce the toxins until the beneficial bacteria can take over again.

Below is a link to my fish blog that has my article on new tanks. It's the only article on there but I hope to have more soon;

http://www.xanga.com/home.aspx?user=Expert_Fish_Help

As far as algae eaters go, one little otocinclus is the most you would want for a 5 gallon. They stay tiny and should have enough to eat. If it seems to be hungry after all algae is eaten, add a tiny piece of romaine, cucumber, squash, cooked green bean, or peeled green pea at night 3 times a week. They will eat at night but the other fish usually sleep. This gives the oto plenty of opportunity without competition until morning. Here is a link to a page about otos;

http://www.fishprofiles.com/files/profiles/otto.xml

At Your Service;
Chris Robbins