Well,

Had my water tested at another store. Measured 35ppm CYA (Which makes sense based on the previously added 6lbs stabilizer) and ~1000 ppb phosphates. They never heard of phosphates masking a CYA test either. Looks like the first store was full of B.S.

All I plan on doing now is adding another 6lbs stabilizer and enjoying the summer. Am not planning on doing anything else about the phosphates.

Pat.