trouble establishing free chlorine level

rweck

New member
Jun 3, 2008
2
I have a 32K vinyl inground pool in central New Jersey. I've shocked it twice and have the chlorinator turned all the way up. My water test results are ph=7.2 ta=110 cya=40 tac=1 fac=0. Please help i must be missing something I'm unable to establish free chlorine residual.
 

JohnT

Admin
Mod Squad
TFP Expert
Apr 4, 2007
9,538
SW Indiana
You are probably fighting algae. To successfully shock a pool, you have to know what chlorine level you are going to. You need at least 16ppm to achieve a shock, and you need to maintain that level until the chlorine holds overnight.
 

rweck

New member
Jun 3, 2008
2
I don't think its algae the pool is actually crystal clear. Could it possibly be that the water temp is to low to break down 3'' chlorine tablets fast enough to maintain a residual. I don't have a heater installed. In NJ the air temp has just reached 80 over the last couple of days but drops down into 50's at night. i checked temp of pool water this afternoon and it was 79.
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
You need lots of chlorine. Add enough chlorine to raise FC to 15, wait an hour and test the FC level and add more chlorine to bring it back to 15. Keep doing this until FC stays the same overnight.