hello everyone, i'm new to this forum... and i have NO idea where else to ask this question... i've had my fish from about 6-7 months now. recently, i added two rainbow sharks to my small collection- they were a gift from my mom and i didn't know about the problem with keeping more than one of these fish in the same tank (big one bullies the small one). but there wasn't much of a problem with this. anyway the really weird thing that i noticed, was that at feeding time, both the sharks lose their fin colour temporarily!!! i have NEVER seen this happen with any other fish. the orange hue slowly becomes paler and paler till there's barely any colour left, and this happens in all the fins but not in the tail. the fins come back to normal in a few hours' time. apart from this strange phenomenon the fish seem to be quite normal......... please don't think i'm a strange person for asking something like this. it's really happening, i'm not playing pranks here...!!