Day Gecko brown???

[Geofft]

I got my day gecko yesterday. Hes a little baby one. Explored hi tank last night. I tried feeding him some cricks today, and he hunted, fast and ate ALOT! When i went up tonight, he had brown coloring. i was wondering what this is. (he was green throughout all the day) This pic he is sort of browny green. After i cam back into the room, he started going green again

[concept3]

many things can cause reptiles to change colors. Temperature, humidity, day/night, and some others I cannot think of right now. If your husbandry is correct and he is eating fine you have nothing to worry about. It generally gets cooler at night and that could very well acount for the color change.

[Stockwell]

Grandis will do that sometimes. I've found when they have to take a dump, or are in dark light, cold or feeling stress,they will darken.
If it greens up with the lights on, and is eating you're fine.