sideways

Hey guys, I have a fire eel now for about 2 plus years and he’s about 14-16 inches. Recently I moved the tank around and put a PVC pipe in there for him because I felt he was getting too big for his self made cave under some rocks I have. Recently I’ve noticed that he lays in there upside. At...

Please help! My jardini started to swim slanted or not straight, I don't think this is bladder problems because it only happens for certain times. For example if i cover the tank in front he will swim straight but if removed he tend to be slanted. Is it the lights or window that's making him do...