Hello, its been awhile since my last post. I have nine Humbug Dascyllus in my 250 ltr tank, im just waiting to have a new 650 ltr tank with a 4ft sump made as the backpack filter protein skimmer setup i paid a lot of money for !Seems i could have got a much better setup from the guys that are making my tank for me now! It sure does pay to shop around!! Anyway, these little humbugs seem to change from white and black to a dark grey almost all black every now and then , Is that normal with these little fellas?They are great to watch, very active little guys!! tnx Blue Tang.