Thanks, that was the answer I was looking for. Just wondering if there are ways to reduce chlorine levels and still stay away from algae. I understand the BG chart and basic pool chemistry. What I don't understand is how some people are able to run FC at like 1-2 ppm in their pools. A friend says he used the Frog Mineral System? in his pool. It seems like a gimic to me with the softer water and minerals, though it would be nice to use less chlorine. My skin gets crazy dry just sticking my hand in to test the water. And after swimming I can feel a difference on my skin. It just feels drier.