I got a pair of Black Paradise fish last week and they are awesome!! Theyre still young so their color is very light. I was reading that they have the ability to change their color semi camouflage style, depending on what color substrate they were over or their BG. I thought it was ridiculous, but Im watching ti with my own eyes now. I have light river stones as the substrate, so he will swim around more of a reddish brown. when he hangs out over the sponge filter he slowly turns very dark. At this point I almost feel like he knows hes doing it. He'll sit on a ledge of my driftwood staring into it, slowly getting darker, then promptly turn around a go swimming around wonce hes very dark. After his color has gone he'll go right back to it, turn colors and go swimming. WTF?!?! haha Ill try to get a video of it today, but its cracking me up so far.