I never thought I'd be posting about low TA, but I'll add my story to this post. Just got mine in operation last night due to construction and replumbing issues. Since my fill water has a TA of over 400, and the water I had hauled in to fill the pool is around 280, I've always struggled with high TA. Last year I managed to subdue it to the 180ppm area.

Since I have algae, the first tests I was interested in on opening were CYA and pH. pH was high, as is normal if I'm not hitting it with acid twice a week, and the CYA was right at 35 just like last fall. Seemed a little odd since I'd had to drain water out once over the winter, and the pool has filled with rain to the top of the skimmer now. Got the chlorine in along with a little acid, and then went to do the full suite of tests on the remaining water from the original sample. I was stunned to see my TA at 50. A 130ppm reduction over the winter with no circulation and a high pH. The real kicker is that if the CYA test is right, it wasn't dilution that caused the TA to drop. Any chance that the algae in the water is causing a problem with the CYA test due to extra crud in the water?