I am a new pool owner (just moved) and learning a lot! I am a bit confused at what has happened with our pool and need advise before proceeding.
Details: Above ground pool, vinyl liner, 15,000 gal, sand filter, chorinator. We used the tabs at the end of last summer without an issue and have continued with a fresh supply (I know the negatives of this and learning and trying to move away from them). We started off the season wonderful with a clean, clear pool and just minor adjustments to bring everything into line. Everything was great until...
I totally forgot to add chlorine tabs to the pool chlorinator last weekend and there was nothing in it. At some point we were not adding chlorine --- probably for 4-7 days. I really thought I had tested the water but my records showed I missed last weekend. So I wasn't surprised to have an FC=0 yesterday.
FC = 0
CH = 200
Other notes: Pool water is blue and clear. We cover our pool with a solar cover almost all of the time and it doesn't get used that frequently. Pool temp is 80. We had a bit of rain so debre on cover went in pool and I vacuumed. I noticed one or two greener spots on the pool bottom which I needed to brush.
What I did: I purchased 12.5% liquid chlorine to add. Added it last night with filter running. I added 3/4 of gallon thinking I would bring the chlorine up to a 6 which would be good for my calculated CYA. I also added chlorine pucks to my chlorinator.
Today I uncovered the pool. Tested. And got the same exact readings as yesterday! No FC or CC! I also grabbed my test strips as a backup and there is no chlorine.
Do you think I have chlorine lock (something eating the chlorine)? Do I need to bring the pool to shock levels? What level would that be and for how long do I keep it at that FC level?
My head is spinning from trying to process all of this information and how do I fix it so advise would be appreciated! Thank you