Hey Gambusia, the Sun Cat that you have, is it one of the cats that are sold as an "eclipse catfish"? If so, yes they do like to hide. The ones we have at work will all try to squeeze into the same tiny crevice or hole in the tank and only like to venture out when it's feeding time or as soon as the lights are out. These guys are nocturnal and unless they have to (or want to) won't come out during the day Pity because they are nice looking fish!