While treating my 2 pet goldfish of 2 years for cotton wool, 1 fish got caught in the filter intake tub overnight. When I rescued him in the morning, he had a red circle on his side from the tube and a severe curved spine. It's been 36 hours and he just floats around the tank just barely surviving. Will he straighten out? The cottonwool seems to be getting under control from the fungus treatment.

It sounds like he could have severly injured. If the back is broken or deformed, it probably won't improved. If it's just sprained, it may improve with time. The red mark should slowly go away. I accidently sucked up one of my goldfish in the gravel tube intake when cleaning the tank a few weeks ago. His face was all red (the blood pulled to the surface). I added some MelaFix. He was back to normal in about two days. Being stuck longer to a filter intake probably was much more severe than that though. You can cover the filter intake with a piece of pantyhose (new or sterilized) or a filter sponge to keep small or sick fish from being sucked in.