I had been having alot of trouble with yellow mustard algea after years of trouble free operation. I was using a feeder with Trichlor pucks since the pool was built in 1998. In 2005 I started having trouble with mustard algea. Leslies recommended draining and refilling due to excessive TDS. Of course the trouble returned since I continued to use the pucks. This year I was constantly getting mustard algea and buying Leslies Yellow Out which worked but only for a short time. My search for answers brought me here where I learned about CYA saturation. After that I had Leslies test the water and they recorded CYA of 90 on one test and 150 on another. They tried to sell my wife the power powder and Phosfree again but I told her to just get the test results. A couple of weeks ago I drained the water way down to relieve the CYA level. Upon refill I was able to hold FC of 20 ppm overnight. My current numbers are:
Since CYA is off scale right now I decided to add pucks to the chlorinator for the time being. How often should I test the CYA level while I'm trying to bring it up to 30-50 (I don't have SWCG)? Also should I add calcium? One of the problems I've been fighting is white streaking on my rosa flagstone under the spa spillway. I spent last Saturday scrubbing with a 60/40 muratic acid solution which helped but not enough. Sunday I refilled and shocked. The pool water is clear since the refill.
What would you guys do now?