For soaking, I also use the "giant" rubbermaids with air holes toward the top. They work great for adult males or dwarfs (15' not so much!). I like them better then trash cans b/c they have more room to move. I let mine soak for 24 hrs or so.

Besides alleviating the dry shed, I think the water provides a positive stimulus for animals that are caged 24 hrs a day. They do seem to enjoy a swim. Not unlike taking them outside to get some sun. Not necessary- but beneficial to their overall health.
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