I just use a toothbrush, too. I have one dragon that likes to poop after I've left for work, then likes to paint the rest of his tank with it. The toothbrush has always worked well, as I was told, when I got my first dragon in 2005, that no soap is good for dragons, so I've never used any. Alot of people use baby shampoo, it is mild, so guess won't hurt, but try the toothbrush first.