I'll admit that I am more than a little depressed today because my fish are sick. Originally my 30 gallon tank became infected with ich when I brought home a few gourami and plants from the pet store. Six out of twelve fish died before I was able to get it under control with medicine, temperature, and water changes. Now my 10 gallon tank is infected. I have no idea how I could have transferred the parasite from one tank to the other, but I must have somehow unless it is just stress that caused it. I only have four fish in the 10 gallon tank, three mollies and one huge goldfish. The goldfish is called Battle Tank and the poor thing is so ill. He just floats around near the top of the tank. I know he has a lot in him because he is eating and zips around when the other fish pick at him, but I still feel horrible. There's just not much you can do to make them more comfortable besides change the water and add medicine. Other than that all you can do is wait to see if it gets better.
I learned not to buy fish from a certain pet store chain, but unfortunately it was at the expense of my older fish.
Update on the fish - I had to separate the mollies from Battle Tank, but now they all seem to be doing a lot better. The signs of ich are disappearing and they are more lively.