If this was related to fluctuant water chemistry, i would belive that the other two leos in that same tank also would be affected... - well they don`t turn white/gray, so im pretty sure this is a result of she bein bullyed. Luckly it is not long before my new and bigger tank is ready, so hopefully more room = less bullying...(?) As an alternative i could leave the victim in the tank she is in right now, and only move the others...
It`s not a big problem though. The other female stress her out now and then... but most of the time she leaves her alone.