Recently while observing my German blue ram, I noticed that on one day he had a clear sort of feces that looked like a hollow tube and today his feces seems to be a red about >

< that color. Is this color change something to be concerned about, either color really, or is it just a result of the flake food I feed him (Prime Reef)?
I alternate the flake feeding's with blanched peas, frozen tubifex worms and frozen brine shrimp.
Also if anyone can help, three days ago I saw my little albino cory sitting near the front of the aquarium. As I watched, his forequarters seemed to rise by itself, as if they were positively buoyant or something

. I've been watching him since then to see if he acted strangely again but he seems all right.
Thank you for your help.