This year I didn't and got myself into a real mess. Last season I went off the reservation and used Tri-Chlor pucks because I was lazy. Over the season the CYA built up and didn't completely diminish over the winter. This year, assuming there was no CYA in the water, I added enough to bring it up to recommended level. By adding more to what was already there the CYA was at least 120+. The only way to lower it is to drain and replace water. I'm at correct CYA now, but could have saved a lot of time and money by sticking with bleach. To start the clearing process my SLAM target was 28! Lesson learned - the hard way!
