I live in the Metro Phoenix area and had a new in-ground pool built 3 years ago. I'm still pretty new to pool care and leaned on the big pool store to guide me...plenty of tri-chlor shock and tablets until after only 3 years my pool was over the limit on CYA and Calcium, even low copper which I have no idea how that got in there. I just drained my pool, did a quick chlorine wash and I am ready to refill and hopefully start doing things the TFP way.