Guido, Carl mentioned that your CYA level is high, but it is the level recommented for most SWG manufacurers. They also recommend being able to run a 2-4ppm CL level with that high of a CYA. I run my CYA lower then recommended, but have no issues with only a 2-3ppm CL level. The theory for this discrepency for the difference from Ben's best guess chart is the superchlorinating effects of the SWG cell. Also I'm going on the tail end of my first year with a SWG. Just keep adding acid as needed. I have to added about 1/2 a gallon twice a week to keep my PH level down in my 30000 gallon pool. Finally don't worry about the high CL level and the SWG. It will still eventually come down to the maintenance level set via the SWG. I would recommend not turning the SWG on and off, just find the correct level and leave it on.