Team, Let's reset a little bit here.
Because your TA is high, your pH is likely rising fairly quickly.
The solution is NOT to add a whole bunch of MA to reduce your TA to target with one big addition. If you take that approach, you may tank your pH.
Let take this approach:
1) Add enough MA to reduce pH by .2, wait 20-30 minutes with your pump running. Test again. Repeat this until your pH is clearly 7.8. This will get your pH into a range you can see and manage. At this point your pH is somewhere above 8, but you have no idea how much. Taking this approach will safely get you back into the 7s.
2) At this point, add enough MA to get your pH to 7.0-7.2. This will also reduce your TA some. You can allow your pH to rise naturally until it gets to 8. Then repeat your MA addition to get back to 7.0-7.2.
Over time, you will naturally reduce your TA.
If you feel the need to accelerate this process, use this:
A lower Total Alkalinity level can help a pool owner stabalize their pH increase. We'll explain how to lower TA with a little help from muriatic acid.
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