My current motor on my waterfall (A.O. Smith Model: B128 / 1HP / 1.25 SF) died. That pump was great for when the waterfall was on during the day with all the kids in the pool, but at night we wished we would have more of a sedated flow (which would equal less noise - think a babbling brook). My thought was there must be a way to control a pump (taking recommendations) like you control a light or fan on a dimmer switch. Is there such a thing?