Im guessing its a gas/air build up in the tail area of the fish. the last 1/3 of the fish is always sticking ut of the water and he swims at an angle cause of it. He will sometimes pull his body to a normal position and you will actually see the tail rise like a fishing bobber would dart to the surface if you let it go from under the water. I have a pick here to show the angle of him swimming. Im pretty sure its some kind of air build up but really what can I do. otherwise seems perfectly healthy



