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
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
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