Brand new here. I just need to be pointed in the right direction. How can I figure up chlorine levels when they go beyond my test's color levels? I just purchased the Leslie's Total Poolcare DPD Test Kit. In other words, the color i'm getting is darker than the darkest purple on the chlorine cell. I have been shocking heavily for a couple days to get rid of mustard algae. No sign of the algae and my water is almost clear, ever so slightly cloudy. I just want to make sure it's safe to swim in tomorrow. I purchased some chlorine neutralizer but I'd like to have the exact ppm number before doing anything else.