Quote Originally Posted by rbposey View Post
Hello and thanks for all your help last year.

My water chemistry is as follow:

Chlorine 4
Ph 7.4


CYA 120
Alk 380
Hardness 100

The water is clear and perfect. Do I need to worry about the last 3 and get these into the recommended tolerences?

Rich
If your pool is vinyl, then the hardness is unimportant.

But with a CYA of 120, you need to maintain a chlorine level of (if I remember correctly) 8 or 10 to 15ppm. Otherwise you cannot count on it staying algae-free for long. You could drain half your water and replace it, which would drop CYA to 60--High, but easier to maintain--5 to 10ppm of Chlorine. But you better add bleach soon or risk trouble.

Alk is very, very high. You should lower it to prevent scaling.

Just because water looks clear doesn't mean it safe to swim in, or that it's going to stay that way. With a CYA of 120, a Chlorine level of 4 is going to have troubles killing the important stuff--bacteria. When algae grows all the Chlorine is consumed by it and there's none left to keep the water sanitary.