yeah, I agree with rally...either loose the flash or angle your camera so the flash isn't bounced back into the camera. OR tape a piece of toilet paper folded in half over the flash to try and dampen it. Either way, awesome cats thar bro!
One last question, why do you have the tank divided? Are some of them way smaller? I've never had my large cats fight when i had them, so i was just curious why you were doin it.