I left my daughter in charge of our pool while we were on vacation over the past week. My test results have been pretty much spot on, except having to add liquid chlorine every day for almost a month. I figured having her add a quart of chlorine every other day would hold things well enough until I returned. She confessed that she only added it the second day (of 6) that we were gone, but that since the pool water was so hot they had siphoned off some of the water and added cooler water several days in a row. When I returned home yesterday afternoon I tested and the chlorine level and CYA levels were nonexistent. pH was perfect at 7.4. I added 1.5 lbs of CYA (as per PoolMath recommendation) and two quarts of 10% chlorine. That was a bit more than recommended, but I wanted to make sure to kill off anything bad. I just now retested and the free chlorine level is still nonexistent. I didn’t retest any of the other chemicals yet. I wanted to post this first. Any suggestions?