Hoping one of the experts can help me out with this question. I work in the industry and test 100+ pools a week. I've noticed when I get a CYA level that is way over 100 the TA test is pretty much useless. I'll retest TA 3-4 times with a high CYA and get different results every time, sometimes ridiculously different results. Why does high CYA affect the TA reading? We use the Taylor K-2006 with titration for TA and CH tests. Is there any way to get an accurate TA reading with a sky high CYA level?
Also, when the CYA is that high I always recommend draining and refilling or switching to a liquid chlorine diet. Almost always customers aren't willing to drain because it's expensive. Is there any other advice I could be giving them they may listen to?