I do not own a Valentino Puffer but my local LFS has 2, and I plan on purchasing one when I get my new tank set up. Since I do not own one I dont know all the exact facts on these fish, but the 2 they had in there store where very active little guys. They cruised around the tank, and when they werent moving they stayed at the top. I dont know what may be wrong with yours? How new is the fish maybe its still trying to settle in? If this keeps up you may want to check your water perameters and if they seem ok go back to your LFS where you bought and ask.