2 fish; 1 sick

Question
For about a year I have had a 10 gallon tank with 2 goldfish, which I won at a local fair, and one small algea eater. Lately one of the goldfish began floating. He seemed like he was having a problem staying stable. I looked it up on the internet, and figured I had overfed by a bit. The other goldfish is a bit bigger, so I figured that was why he wasn't affected. About 2 days later i checked up on him since he seemed to be swimming around and feeling better. When I looked at him, his left fin had a red spot, likea bruise or something, his mouth looks like it is lined in black and his face is beginning to lose color. I have not seperated them yet because I am not sure what it is that he has. Today, I noticed he was sitting on the bottom a lot. Every now and then he gets up and swims around. another odd thing is that he has been nudging the algea eater to make him suck on him. I heard this could be a way to suck out infection, but wasn't sure. Oh yes and he sometimes goes to the top and spits water. The bigger goldfish also seems to spend a lot of time at the top. I wasn't sure if it was due to poor water quality? i just cleaned the tank and added all fresh water about 2 weeks ago. Now about the details... I have a whisper filter, which i just changed because of being worried about water quality. I usually change the water when i clean the tank about once a month, or if it gets too dirty before then, but dont replace water until then. The tank usually stays at about 72-74 degrees. I did buy new plastic plants and gravel about a month ago and put them in then. I washed them first of course. So please help me. I unfortunately not of those that will spend too much on fish a got at a fair, but i also dont want him to suffer or get my others sick too, so please help!! thanks!

Answer
Hi Brittany;

All the vigorous cleaning of the tank, filter and replacing of gravel has probably caused your tank to go through the "break-in period" as if the tank was new again. Waste toxins have risen and the smaller fish is just affected more easily, for whatever reason. They suck at the top because it is harder for them to get oxygen right now with the toxins elevated. The beneficial bacteria that normally would control waste toxins is now gone or greatly reduced from so much disturbance. This beneficial bacteria lives on decorations, gravel and especially in the filter pads. Your fish were probably smaller when the tank was actually new so it wasn't as hard for them at that time. Bigger fish means more waste, more waste mean higher levels of toxins. The bacteria colonies will re-establish but it can take several days or even weeks.

To help the fish get through this until things stabilize again, make a 25% water change right away and do them every day for several days. The fish should start feeling better in the next couple of days. To know if the bacteria is getting back to normal, you will need to get two test kits from your local fish store. You need to know the levels of ammonia and nitrite so test every day. Every day that one or both are elevated, make a 25% water change.

Goldfish are very messy fish that actually need a minimum of ten gallons just for one, 20 is better. You might consider getting a bigger tank for them. They would do much better in the long run, especially with the algae eater adding waste too. A 30 gallon would suit all of them just fine. Remember that the new tank will go through the break-in too. It is manageable though and there are some precautions you can take to get them through it safely. Here is my web page about it to help you know more;

http://www.xanga.com/Expert_Fish_Help

All tanks actually need a 25% water change once a week, every week. Gravel vacuuming should be done weekly too. This is especially important with goldfish. Weekly 25% changes keeps the water quality more consistent and helps the fish be much healthier without stressing the system or the fish. A whole bunch of fresh water at once seems like it would be a good healthy thing, but it can shock them. The water chemistry in the tank can be very different from fresh tap water if it has been too long since a change was made.

I hope they feel better soon...

At Your Service;
Chris Robbins