Why do you want your TA at 120?? Most folks are trying to lower it a bit from that......
You may have algae=green. Just because your FC is 7.5 *now* doesn't mean its always been so..... so either jump in to a SLAM process or do an Overnight Chlorine Loss Test.
A CC of zero is not indicative of no algae. CC is primarily created by the oxidation of ammonia based compounds by chlorine. Algae typically produces little to no CC when oxidized. Also, CC rapidly burns off when UV hits the surface of the pool.
You need to follow the SLAM Process. Lower your pH to 7.2 and raise your FC to 28 ppm and maintain that until the pool is clear and you pass the Overnight Chlorine Loss Test
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Welcome to TFP! For a wealth of pool care information please check out our free Pool School. If you are in need of specific help then we encourage you to Register and ask us here in the forum!