Trouble lowering alkalinity just before closing

[HiddenRiver]

We had the pool replastered one year ago and continue to have trouble bringing the alkalinity down even though I am following pool math recommendations with lowering pH. I have brought the pH down to 7.2 but alkalinity is still at 160 and Calcium hardness is at about 300. Do I just keep adding acid to get the alkalinity down? Is the pool still curing after one year?

 

[mknauss]

After a year your plaster will be fully cured.

If your TA will not drop, then alkalinity is being added somehow. Either by chemical additions or fill water.

 

[Texas Splash]

You look to be on a well. Well water can be often times have a high TA and CH level. You can test that well water to see. When trying to lower TA, be sure to let the pH rise to about 7.8 - 8.0 THEN use enough muriatic acid to lower the pH to about 7.0 - 7.2. That large swing should have a better impact on your TA. Something to consider next spring when you open.