need some cowfish help

[chrisd1986]

I have had a cowfish for about a month now and everything was going great. I recently have put in a 20g sump to my 75g tank. My tank is not drilled and had no overflow so I had to make my own I used 1 1/4in pvc for my drain and 3/4 with a sicca 3.0 return. I came home yesterday to find my cow missing after a quick panic I found him in my sump in the filter bag he had been sucked down the drain pipe which I did not think the water level was high enough for this to happen once cleaned off I placed him back in the main tank and turned off the pump ran out to the lfs and got a grate to put on the pipe so this cannot happen again turned the pump back on and everything was fine the cow didn't seem to be injured but did look a little stressed so the lights went out for a few hours. Later that night about 8 hours later I was watching my tank and noticed the cow was missing again. Looking around I found him stuck the grate on the drain pipe removed him and again he seemed just fine. Went to bed cow was still swimming and now avoiding that side of tank. when I got up this morning he was again missing I checked the pipe and he was not there I finally found him up against the glass and some rock I freed him and he swam off but then began getting pushed around by the water flow around in a circle off the glass as he moved in front of the return. I did remove him from the tank and the only qt tank I have is a 1g he is still a baby only 1/2in long. body wise he looks good still yellow kinda has a green tint but has had that since I got him I did notice his left fin is not moving and looks like it may be swollen just wondering if there is anything I can do for him he would not eat this morning when I tried to feed him and he is just sitting on the bottom of the tank
water is good with one exception that I am fixing is my no3 is high I have done 2 10g water changes and will do another and vacuum the tank bed tonight when I get home all other fish are doing just fine I did notice a dead turbo snail that I just got last week. Any help is appreciated[/COLOR][/COLOR]