Hey, I have a 21L tank that has been set up for about 4 months and it houses 2 Neon Tetras, 5 Gold Neon Tetras and a Corydora Catfish. Yesterday night I noticed that my catfish is having huge issues sitting on its belly on the bottom of the tank, it kind of tips to the side, falls over, then swims of to another part of the tank where this happens again. I originally diagnosed it as swim bladder disease and have fed it peas instead of its normal food since then to relieve constipation if it had it. Nothing seems to have changed. When I did a w/c yesterday morning (before its problem), it swam really fast to the top and almost seemed to jump out a little, then it had its buoyancy problem that night. I don't know if it had sucked in lots of air or is just constipated and bloated. Water temperature is 25C, pH is 7 and I don't have an ammonia kit. Please Help! I am trying to add a photo so you can see if it's bloated.