I bought a dwarf flame angelfish yesterday, I put him in my tank last night and he seemed to be fine, woke up this morning, fine, then out of no where he started swimming erraticly all over the tank, breathing fast and is now lying behind a rock, breathing just as fast. I tryed turning everything off, then I tryed to add an air stone in case there was not enough oxygen. Hes still there, just lying there and I don't want him to die. I'm going to do a water change but I have a clown and a firefish and they are not doing the some thing, its only the flame angel. please help asap!!!