Baths?

[sunset]

I have read that it is good to give your beardies warm baths every now and then, but how often? And I think the water temp should be ~95*, right? I don't want them to develope any skin probs from being too moist, but they loooove the bathtub, it's so funny to watch them swim like little alligators. I have been doing it about once a week, is that good, or should I do more? Oh yeah, and they always poop when they are ready to get out, so I think it is helping them pass sand, ( I just recently moved them from playsand to coconut husk after being told about impaction risk) cause it's gritty when I wash it out. Would 3 or 4 times a week be ok? Say ~20 minutes at a time?