Is 60 oz liquid chlorine per day standard for a 9,000 gall pool

[CarlD]

A drop of 3ppm is a lot, espec with that CYA. Have you tried shocking the pool to about 15ppm and seeing if that solve it? Alternatively, you could raise CYA to 60ppm and run a minimum FC of 5ppm. Your sun is intense, but in the summer you get less of it than us in higher latitudes--in NJ we are due west of NYC, which curiously, is EXACTLY the same latitude as Madrid (check it out). We went to the UK for a wedding a few years ago in July and the sun didn't set until 10:45!