a friend of mine has rescued an 18" beautiful redtail catfish from a friend. he came from an overcrowded 125 gallon tank with very poor water conditions. he is turned almost completly upside down, breathing heavy and is arched. he is in a clean 75 gallon tank right now and is not improving. is there anything we can do to help the poor fish? my heart breaks everytime i look at him.(he's been like this for 3 days)