Mud Bath query??

If I wanted to make a mud-bath in a fairly large paddling pool whats best to use??
I'm guessing powdered clay would be the best but how much/where from??
How long could I keep it in there??
And how is best to dispose after use??
Any help would be great!!

I'm guessing powdered clay would be the best but how much/where from??
How long could I keep it in there??
And how is best to dispose after use??
Any help would be great!!
