Hi I have a beautiful goldfish who for the last month has been sitting on the bottom of his tank. I have tried all the water changing advice 25% clean and full clean. I put something in the water to make it safe etc but he still sits on the bottom looking very sad. I also noticed hes not eaten for weeks as I am scooping out old food and that his mouth seems fixed closed. Ive tried starving for a couple of days and also tried peas. I dont know how he is still alive is there anything else I can do. I does have a burst of energy abut 2-3 times a day where he zooms around the tank but he looks very sad.