I am having trouble maintaing FC level.

[OcneeDawg]

FC 3.5
TA 80
CH 250
ph 7.4
cya 70

I have a pentair IC40 vinyl liner. We went on vacation last week and my nephew was looking after the pool. They splashed a lot of water out of the pool and pump was catching air not making C. The water is very clear but I can't maintain FC level. I am at 3.5 with running in super chl mode. My question is can you need to shock pool even if it is clear?

 

[freqz]

Sure you can!

Run the OCLT first to see if you have something eating your FC.

 

[Richard320]

You sure can. Use bleach. And it is safe to swim in up to shock level, so you can target 28 and still be okay to swim!

If you lost a lot of water, you also lost the corresponding amount of salt and CYA, so you ought to confirm those.

 

[OcneeDawg]

Thanks for the advice I have had my pool for a year now and this is the first time I have had to shock it