We built our in-ground chlorine 13,000 gallon pool in 2013 and should have registered with TFP sooner. Once again as in every spring, dealing with high CYA and chlorine lock. Hope to learn and feel more confident about water analysis and to find an alternative to the 3 inch chlorine pucks. Have always maintained it myself and check the water with a simple BioGuard multi-test 1200V kit I got from the pool builder. Thinking to get your recommended test kit. Thanks