Strange New Behavior

[CillyNM]

Hello Everyone. After a few successful weeks of not killing our first ever fish (5 tiger barbs) I have started to notice a behavioral change in one of the larger ones. Of the five, I believe he is the oldest, or at least is the largest. (he? she? can anyone tell?) Lately when I turn the light on in the morning, the fish start swimming more actively and I always count them (lol) and I seem to always have to look for him - I always find him "hanging out" in the corner where the filter pours water back into the tank. He sometimes swims in circles backwards and is showing very little interest in eating, though I have seen him eat. Is this normal behavior? Should I be concerned? Or do you think he has just developed an addiction to the whirlpool action of the filter? (lol) . . any insight would be most appreciated as I don't want to lose this fish, I didn't think it was possible but I've grown quite attached to these little guys!!

Cilly

 

[canarsie11]

Males have more orange snout.

Sometimes turning on light in morning can shock fish, if room is completely dark. Most people do it anyway.

Even if room is getting some light can still shock them. I doubt it is that but it could be

 

[WILDER]

Please post test results to rule out water quality, in ammonia,nitrite,nitrate,and ph, there is definately something not right with him, they are jumpy when you turn the light on in the tank.