I am so new to this. We se to have a pool but that was years ago and I used the clorine tablets. I have an aqua chem testing kit until I can get a better one. It has CL and BR and Ph levels only. I used the calculator and I put in what it said to but now my CL level is way to high. I think the problem was this kit reads 1.0 to 3.4 as ideal CL level and mine is showing 5.0 now. The Ph is showing on this kit idea to be 7.6 and my ph is 8.2. My pool is vinyl with 4000 gallons of water in it.