Flash Testing, is it Accurate?

We have probably all done it or at least been tempted to use Flash Testing. That is when you drop some Phenol Red and OTO into a pool and estimate the pH and chlorine level. But is flash testing accurate and a good idea? Leslie’s Pro: Pool Service Pro, open a Wholesale account today! Customer referrals, free cleaner repairs, free water testing, open 7-days a week. It is fast and easy to become a Leslie’s Preferred Pool Care Provider. https://lesliespool.com/commercial-services.html/?utm_mediu...