High MA Usage

[phalcon51]

I've been having to add about 32 oz. or more of MA roughly every 3 days to keep my pH between 7.5 and 7.8. The pool was re-plastered in Sept. 2010, so about 7 mos. ago. Just wondering if this would be considered excessive and what I should do about it.

Latest test results from my Taylor K2006:

FC - 5
TC - 0
pH - 7.8
TA - 80
CH - 300
CYA - 60
Salt - 3550
Temp - 72

Thanks for any help,

Gary

 

[XsAllOverIt]

They say it sometimes takes close to a year for pH to settle in a plaster pool. Welcome to the club. Mine was put in last November and I'm adding roughly the same amount.

 

[JasonLion]

There will be some PH increase due to the plaster continuing to cure for about a year after the plaster was originally applied.

You will also be seeing some PH increase because of your TA level. Lowering your TA to around 60, or allowing it to come down to there on its own as you continue to use acid, will lower the amount of acid you need to use at least somewhat.

 

[phalcon51]

Ok,I guess I'll work on lowering the TA some more. i'm planning to add borates as well, up to 50 ppm. Will that help to stabilize the pH somewhat?

 

[JasonLion]

Borates will cause the PH to change much more slowly, but they will not change the total amount of acid you need to use. You will be using more acid each time, less often.