blenny question

[nightfire]

hey guys yes my blenny seems awesome...pigging out and pooping a crap load lol my question is what does him/her showing off its stripes means....its a sailfin blenny and i only have one of it in the tank with 2 clowns...all 3 hang with each other and all so why at times does he/she shift colors like that...looks cool though

 

[NeedBiggerTank]

Our lawnmower blenny would turn nearly white when he was sitting on/near the sand and turn almost black when on the rocks or sitting on something dark. This seems to be a fuction of camoflauge maybe? But totally normal, as far as I know.