I have a delima. I have a 15inch Pleco that I have had for about 3 years now. He has been with Goldfish since I got him. Recently the Goldfish have passed leaving him alone. I have recently redone the tank, new gravel, new decorations, and a canaster filter and now all he does is hide. He used to swim around, flare his fins and attach to the side of the tank when the Goldfish were alive. I wanted to wait to get more fish. I can't decide what to get that won't pick on him. I don't want any that are aggressive toward him. After all he has survived me and I want him to enjoy himself. Should I worry that he is hiding all the time. I have checked the water and it is good. Or at least I think for a Pleco. Could he just be lonely.