Catfish appears to have scrapes on its belly

I just noticed my fat a-- banjo cat trying to swim around and it lookes like his belly has 2 places that could be from rubbing against rocks.

Does this sound like what it may be?
Should i medicate the water for him?
Should i remove my plants and other fish temporarily and turn my tank into gravel/sand instead of all gravel?

I am going to cut back on his food i think. He always goes crazy as soon and as the food lands anywhere near him and he scarfs it down within seconds. So i didnt think he was over fed until i saw him trying to swim upwards and it wasnt working out like he had planned (also when i noticed his belly against the glass and the 2 light spots on his huge belly).

thanks!

Do Banjo Cats shed there skin? I will look into this.

It does shed its skin afterall! If this is what it is doing, it will be a relief. I still plan on adding the sandtrap idea that Waterbaby gave me so it can burrow. It seems like you told me they shed before, but i ruled that out and thought it was his illness since it died the next day. I had the same illness on a pleco i had a while back. Anyway, i didnt look into it because of his death.

here is where i found out the info. incase someone else is interested.

http://www.planetcatfish.com/cotm/1997-06.htm

thanks