- Jun 22, 2014
- 52,028
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Let's hope not. At some point you seemed to have some CYA, so perhaps there is still some in there, just not enough for a good test. But add about 20-30 ppm as soon as you can. Use the sock method. Retest in a day or so. If your CYA jumps to 40, then increase the FC to 16.
