every month or two throw away all the bark (are you using cypress?) and wash the inside surfaces of the tank before putting fresh bark in. This will keep bacteria and other pests down. You should also wash out the water dishes and hides
I wash the hides when I do the bark, but wash the water dishes AT LEAST once a week. I also wash out the water dishes if I find any poo in the cage since he may have gotten it on him and then dragged it through the water dish.

you asked a good question