Has anybody ever done a running water feature inside a snake cage? I think it would be neat to have a little waterfall or something into the snake's soak pond, but need help finding a water pump and suitable filter. I checked out the fish tank filters, but they all get their water by sucking it out of the top of the tank...

Also, with a charchoal filter, would the water still need to be changed daily, or would that extend it out to every several days/once a week, and an extra change if it poops in the water?