- May 3, 2014
- 58,745
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
The shock level water is flowing through that filter. It does not harbor live algae. No way.Agree that the filter could be what's contributing to the FC loss. I'd open it up and see if it needs a good cleaning.
Aubade - you said you found the pool with 0 CYA this spring and added to 70. You have tested that again recently, right?
CYA does degrade naturally about 3-5 ppm per month. It also can be attacked by a bacteria that creates ammonia that take a significant amount of chlorine to eradicate. But once the pool holds FC and CYA, the bacteria is dead.
Good luck.