ALSO, I think some frogs just have different natural tendencies! I have my two WTFs in the same tank, with the same conditions, and one tends to stay green to light blue , and the other tends to go from brown to olive green. Course this could be because Kibbits (the browner of the two) prefers to stay on the warmer/dry side of the tank, and Igby (the bluer one) tends to stay on the cooler/water side. No matter how many times I change up the habitat with various combos of branches and vines in different places, they seem to always end up in their preferred sleeping sides (Kibbits hiding away inside some branch or log, and Igby sleeping on top of some leaf or log above their pond).