Water Gardening: My new hot tub pond, 0 by silverfluter

silverfluter wrote:
DH here.... the problem, or concern, since it is only gravity "pulling" the water thru the drain hole, will gravity pull 3000 gph thru a hole 2 inches in diameter. That is the technical question!!! I can cut the hole larger to accept a larger bulkhead fitting. We just want to be sure the pipe or tubing will gravity feed enough water. My idea originally was to cut the hole wide and flat, maybe 2 inches tall by 7 inches wide, to be sure enough water will be able to feed thru. We would attach the lower pond liner to the outside of the tub, just below the cut, no pipes or tubing involved. I was thinking of using two-sided tape to attach the liner and then covering over the outside with black foam to be sure to get a good tight seal. The outside of the tub is rather smooth,no voids, just not polished like the inside, so the tape should adhere rather well.
As far as the exposed part of the tub that will be above the water line, we will "black foam" attach rocks to the tub down to the waterline. We had to do something similar with the preformed fiberglass liner we are using for the upper pond. See attached pic