plumbing drain and return questions.

[WarDog]

IMO you should do a 1" drain with a 1" gate valve (as low as possible) and a 3/4" emergency a la Herbie. If you want to use that large of a return pump you will need to dial it back for sure and perhaps even add a valve on your return line. Also you could tee off after the pump and run a manifold system to feed reactors, chiller, UV, etc, and even have a line feeding back into the sump to relieve some pressure on the pump. The more restriction you have on water leaving the pump will significantly shorten its life.