strips

I’ve tested via liquid my CYA and have never seen anything below 100. I so wish there was a more definitive test like counting drops. I’ve also tested using two different strips and they both come back 50. I tested the strips with tap water and they correctly showed “0”. Which should I trust...

I've been using dry acid for many years. Now I'm back to using muriatic acid (14%). My concrete kool deck needs to be redone and I want to make sure the sulfate levels in the water isn't high enough to damage the new deck from all the splashes. I looked here for strips: Macherey-Nagel, 91329...