Zaphod looks weird

[LegoBetta]

I have a twoish year old (given to me by a customer in a vase fully grown) crowntail Betta male. He lives in a 2.5 gallon filtered heated tank that is within normal specs. Last week I left town for a few days. Dropped a weekly feeder in the tank and left him to be supplemented by a friend who fed him his normal betta pellet diet twice during the time I was gone. When I came back I also noticed the tank light had blown but this is probably unrelated. Today I fed my tanks brine shrimp and then did my tank cleanup when he fled the gravel vac I noticed how thin he had gotten. This large fish has become mostly head. He also has loose scales near his face. His feeding is normal and his activity and color are great. I was going to catch him in a small non bowfront tank to post an image but hes feeling up to being difficult about being netted and I didn't want to stress him. Any ideas?

[callistra]

Feeders are not good for tanks. They will cause ammonia to build up quickly. You may have created a water quality issue doing this.

http://www.bettafish.com/showthread.php?t=49233 More info is needed. Photos would be helpful.