My pool is approx. 20,000 gal. Had it drained and cleaned last spring after five years. The CYA seemed to measure very high after the company drained it. Thinking this guy may have put excessive stabalizer in it. Now it’s so high I can’t even measure.I use liquid chlorine and 2- 4 pucks a week. Appears I need to drain most of the water out and start over. Will that take care of it?