I would not put any gravel in that they could swallow. They will eat rocks. I worry about impaction. -Rick ADestroyah@… wrote: On a different topic, I’ve taken Rick and Chun’s advice, and rid my tank of sand, and now the weird colored scales on the female seem to be fading away, and she seems to only be going into a normal shed. Maybe it was a normal shed all along, and I’m being jumpy, but oh well. The bottom of the tank now has common gravel which the turtles seem to like nibbling on.. Ugh.