So I use the BBB method, CYA got jacked up due to using leftover Di-chlor powder before the switch this year. I literally opened up the pool this year to a black swamp that smelled like a sewer. I mean I really chucked that stuff in there to clear the water. The CYA was around 20 when I started adding Di-chlor powder. After prob 20 pounds of "shock" powder and 20 pounds of "regular strength" chlorine granules I was at 100. i always knew that CYA was a problem, but had thought that the upper limits was 200ppm (pool store). i am at somewhere between 90 and 100 now. When I dilute the sample 50/50 I get 90. Without dilution I get around 100. My water seems OK, though. FC stays around 7. I bump it up a little before we swim and add a little more at dark. There is little chlorine loss overnight and throughout the day. The water is very clear...you can see a quarter on the bottom of the pool and the sunlight dances around on the bottom. CC ranges from 0 to .5. I think it may have been close to 1 once the sample turned almost clear on the first drop. Draining water is not really an option and I really do not care to buy and use that much bleach. So does anyone else have experience or suggestions on maintaining a higher CYA pool?