water is a turquoise blue color


Jul 3, 2010
It has been this bluish color for about 2 weeks now. I have been taking it to the pool store and all they tell me is keep adding 2 bags of shock and that the ph is a little high and to lower it. Here are my test results (from the pool store) from this morning. It is an 18000 gallon above ground pool with a sand filter.

CYA: 61
TC: 2
FC: 2
PH: 7.9
TA: 110
Total Hardness: 197
Quat: 3

What should I do to get the water clear? I have been to Wal-mart and stocked up the the chemicals recommended by this site as I am sick of paying the pool store hundreds of dollars a year.


TFP Expert
LifeTime Supporter
In The Industry
May 20, 2007
SWSuburban Chicago, IL
Read How to shock your pool in Pool School. Your FC level is too low for your CYA level, and it sounds like you need to shock. Can you see the bottom of the pool?

You need to lower the PH down to 7.2 with Muratic Acid. This is the first step, then wait a half hour and add the bleach/liquid chlorine to reach shock levels.

Do you know how to use the Pool Calculator?


Jul 3, 2010
No we can't see the bottom of the pool at all. I have been playing with the pool calculator, I still have a lot to learn. Thanks for the help.


Platinum Supporter
LifeTime Supporter
Jun 28, 2009
Is it the bluish color when you put in a clear vial, or only as you look at it in the pool?