So the sticky post from Nitro says 20-30 for CYA in a spa. How do you even measure that? My Taylor test kit can't measure below 30. I can still see the dot at 30 so I know it's less than that but no way to know how much. He says to measure it by how much Dichlor you add but I have a problem with that. We use our spa a lot, sometimes 3 or 4 times a day and every time some water goes out with us. I have to add a little water every week so the CYA is constantly falling. I'm thinking of raising CYA just so I can measure it.