I tested for CYA using the CYA reagent and vial with the black dot on the bottom. I transfered the liquid to the vial and noticed the water was so clear I could see the black dot even if i filled it beyond the graduation level on the vial (30). So this indicates I have at least <30 ppm of CYA. The water wasen't even the slightest cloudy beyond 30. So I can only asume that it could be 20, or 10 or 0. Based on the pool calculator on a 13,500 gallon pool to raise by CYA by 10ppm It indicates I need to add 18 oz by weight of CYA or 19 oz by volume. I'm thinking (just to be safe). I should add cya in increments of 10ppm until it registers on the test (is supposed to take a week). Then I can go from there.
I'm also curious on the values the pool calculator is giving me. OZ is a measurement of mass. So I add 18 oz? how do I add 19oz by volume? What does that mean????