Can I use them both at the same time? I use plain bleach most of the time. But if I'm gone all day or longer I want a way to make sure my chlorine dosen't get too low. So on the days I wont be there to ad liquid chlorine, is it ok to put a puck in the skimmer basket? My cya is about 40. about how long doing this would it take to raise cya too high? Thankyou. Filix.