Decreasing Total alkalinity

[Sharkster]

I have been using PH- to bring it down, managed to bring it down by 25 yesterday to 175 but it is back to over 200 again today, but the PH is now 7.8 when it was over 8 before.  Should I be using something else to reduce the TA.  I believe the active ingrediant in my PH- is Sodium Bisulphate or something.

[Poolguy]

I've answerd you on the other thread. Leave your TA alone .. its ok

Bring down the pH though 7.2 -7.6, use Dry acid, hydrochloric or sulphuric acid.

 

Andrew

[Sharkster]

I took a reading this morning and my PH was at 7.3 and TA 183, which I thought was fine.  Went out for the day leaving the cover off the pool and it rained heavily and now my PH read 8 and TA 203.  I have read the PH can be increased by aerating the water and rain does just this.  Is this why my PH has gone up so much?  If so, is it back to more PH- to solve the problem?  I have an above ground pool with a vinyl liner and 11M cubed of water.  I know sulphuric acid is better at reducing the PH but I am not sure it is suitable for a vinyl liner.  My PH has been constantly on the move this week, I get it down with PH- and then it increases again.  Please help!!!!!!!!!!

[buckdendave]

The vinyl liner won't care whether its any of those options, as long as whatever you add is properly dispersed and you don't add too much.  The pH- liberates sulphuric acid in any case when it reacts with water, but in my opinion its always better to add hydrochloric acid for reasons that I won't go into.  Just take care not to spill any or breathe the fumes.

Are you sure that your pH reading is correct?

Dave

[Sharkster]

I think so.  I am using a digital pool tester.