i have a sick fish, its an upsidedown catfish?

[Twist]

i have had it for about two years and it has always been healthy but in the past two days it has begun to act strange, it is hanging out with its nose to the surface and it is moving slowly , its skin is all blotchy ,large yellowish areas where its normal skin color and pattern is gone, ive seen it get small areas like this from other fish attacking it or from scraping rocks but this is over at least 25 percent of its skin. what sort of things could cause this? what do i do? i clean the tank weekly as im supposed to and do partial water changes, all other fish in the tank are thriving.
its also not eating, its like it trys to but its paralised or something,it just slowly treads water.

[Brandy]

It's probaby old and at the end of it's life. sorry bud, I thinks his time is nearing.

[~*ToRoNtO-gUrL*~]

thats crazy babe

[Darryl R]

Maybe the fish attacking? I mean 2 years of fish abuse :/.... it takes a toll.

Plus upsidedown catfish have to be in shoals of 3-4.

25% water changes weekly.

[dpepperdrinker]

Flush time

[JesseKlinethegirl]

o you have a filter on it?

this might sound odd, but i had a fish one time who had lived with a filter, and when it broke, after about a week, he began to swim backwards and upside down, and it turned out that it was because there wasn't a filter, and therefore less oxygen in the water.

i really hope that helps.

id cry if i had to watch that. no lie.