I need to do a complete drain due to high CYA and calcium hardness. I have a Zoller 1/3 hp submersible pump (40gpm) and a 5/8” garden hose. Hose run is a lengthy 135’. Lift is about 5 1/2 feet. Pool is 10K gallons, but I’m just looking for a flow rate….I can do the math. Has anyone done this...