Okay, no lashes with a wet noodle--but when they put my pool in last year the Trident UV Sanitizer was part of the deal. It doesn't claim to be the cure all--my pool manual says a sanitizer is always needed. But here's the weird thing--they recommend only a free chlorine of 1-2 ppm. They want the CYA 30-40 (that's fine but would be hard to keep with the trichlor puck dispenser they installed) and the TA 120-150, a little higher than this site says. The "best guess chart" on the site says I would need a minimum of 3 ppm with a CYA in that range. So do I dare keep the level that low? To me, the UV sanitizer is sort of like a "polish' for the chlorine that's doing the bulk of the disinfecting. It just might help and probably doesn't hurt. Also, they want me to use some goofy product called "Aqua Finesse" tablets once a week. I researched it since no ingredients were listed on the tub. It has "sodium carbonate" and "sodium silicate" and "sulfuric acid aluminum potassium salt dodecahydrate" What's up with that???!!!!!