My Lima is about 5 1/2" and I had him in a 48x18x26 with the fish in my SIG, his rear fin is torn in a couple of spots so I put him in a 20G where I keep the rosey reds...Am I overreacting by putting him in the smaller tank to let his fin heal? Hes a very healthly looking fish and he just molted today. There are tears on the top, middle and bottom of his fin, he just keeps swimming and swimming against the glass...One of the tears is close to his flesh, I put some extra stress coat in the 20, added salt and raised the temp to 84. Sound good?