If your Alk is that high and you have a lot of Calcium Hardness, you may have trouble with cloudy water. If you drop your PH a little and get some aeration going, you can drop the alkalinity, but you'll probably have to keep after it if your fill water is that high. It doesn't take a lot of CYA to reduce your chlorine demand substantially, you might want to run the feeder pretty strong and run the pump into the evening a bit so you have some chlorine in the pool overnight to keep things well sanitized. With very low CYA, I'd shoot for a reading of 2ppm over night (measured in the AM) with a residual of about 1 ppm remaining as the sun comes off the pool in the afternoon. I'd test 2 x per day (AM and PM) unitl the CYA starts to build and you are able to turn the feeder down some.