I have one in one of my tanks... along with a fogger. I use the waterfall a lot... they seem to like it and drink from it. I only use the fogger when they are shedding.
Smart Idea. I know that still water can have bacteria grow faster v. running and moving water so this would be perfect especially next to there moist shed. Thanks!
Keep in mind that moving water will release more humidity into the air than standing water will. I'm not sure how sensitive to humidity Leos are but I know that the humidity levels should not be super high. I would just recommend keeping a closer eye on it if you used a waterfall of any type.