When is the best time to add chemical to the pool? During the late evening hours or early morning? The testers recommended to raise the Chlorine a bit and to raise the aklanity up? No one will be swiming in the next 20 hours. Temperature of the water right now is about 80 but rain is expected in 24 hours. Or maybe I should wait till the rain passes? I just want to get the most value for my money.