Well, my box turtle likes to spend most of his time in water. I have a rubbermaid container for the water. The container itself doesn't get much algae accumulation but the rock that is in there for her to use to get out does. And now, it is even starting to accumulate on her shell. I change the water daily, or whenever i notice she has messed it up, whichever comes first. I also add AlgaeFix drops, which i think is the reason there is no accumulation on the container itself, but i would obviously like to eliminate it altogether, especially off her shell. Does anyone know of anything i should use to accomplish that? Also, what is a good way to get the already existing algae off her shell without harming her? If anyone could help, that would be great! Thank you very much!