I have a 27 ft round AGP and I have just purchased the Intex SWG from walmart. It is the new one with the copper electrodes. I am a little unsure if I should leave this connected as I have read a few posts saying that copper is a bad idea for pools. Is this the case with AGPs or just of tiled inground pools? Also I'm not sure if I should put a check valve between the SWG and the heater which is about 6 feet away. I will run the SWG for about 4-5 hours a day and the pump for about 6 hours.