Let me tell you all how proud I am of myself! It was 27 degrees yesterday and I decided to drain and refill my tub! After a few glitches(like I had to defrost the hose in the tub before I could start draining) the whole process took me about 3 hours. Anyway, my question is...I filled the tub and added metal out yestarday afternoon. It says to wait 48 hrs before adding dichlor. I was able to adjust my ph 3 hrs after the metal out. Does anyone know when I can start adding Calcium Hardness?