Check the humidity and add a dripper. If he drinks right away when you offer him water hes not getting enough. Also check his urates...are they white? Orange ones suggest dehydration.
You will be better off propping the cage up on some rack and putting a big bucket underneath...possibly a big rubbermaid container. You should be misting so much that its dripping all over.
It could be a lot of things but im a firm believer in the fact she needs a lot more misting...this is how they clean their eyes. 30 minutes a day at least. Like i said it could be a lot of things so you need to show a pic so members can view her overall health.
You can do a misting system for under 60 if you have access to a laundry tub faucet that has a threaded faucet. Toro misting nozzles...1/4 inch tubing....lawn sprinkler timer.
Ok pinki is wrong. Those are excess salts hes getting rid of. Don't worry this is natural. Bigger problemis the waterfall. Get that thing out of there immediately. It breeds bacteria.
They thrive outside. I would bring them in if it gets over 95. If you have enough foliage they will find shade in that. When the temps are close to 90 here i make sure they get a 30 minute shower every 4 hours. When the temos are closer to 80 i will do 2 showers a day. I use stick tongue...