Just pulled cover off.. green swamp water

[slade8200]

If my stabilizer level was at 50, why is it important to not let the chlorine get below 3?

[Watermom]

Chlorine levels are based on CYA levels. If you haven't already done so, please take a look at the Best Guess Table in my signature below. If you drop below the necessary chlorine range, you risk an algae bloom.

[slade8200]

I looked at that before but didn't see why the ranges changed like they do. I guess algae is the answer. Does the cyanuric acid level decrease slowly with time?