I have a TF-100 but haven't been using it b/c for 2 months now I was expecting to drain the pool any day b/c of landscaping I'm going to get done. I have just been winging it so far, just using the OTO test to make sure I had at least the minimum FC. It's worked out so far.
Well, now that I KNOW I'm taking it down within the week, I decided to test my fill water and for jollies test the pool water and play if I felt like it.
CH 130 (doesn't matter)
Ph below 6.8
TA 20 (totally surprising)
CYA 130 (oopsie!!)
I was just throwing in dichlor b/c I had some laying around and I thought the fill wasn't going to last anyway. Wow, it's higher than I thought.
Anyway, the two things I didn't expect are:
1) The TA drop from fill 120 to pool 20. I didn't have that last year. Don't know what happened. For fun I added baking soda to raise it. Of course, I input the wrong # of gallons in the pool calculator. So it jumped more than desired. I was shooting for a first step of 20 to 70. I ended up with 120. Even when I corrected the gallons and played with the target TA until the baking soda add matched what I put in... the target TA for the oz I put is should have been 90. Don't know why it went to 120.
2) I added the correct amount of 8.25% bleach to bring FC to 20. Tested it and was spot on. That was in the evening. This morning it was 12ppm. I added enough this morning to bring it to 16ppm. This evening it is back to 12ppm. It is difficult to figure out what is happening b/c in addition to whatever organic material is already in the pool, we had 1-2" rain last night and .5" this afternoon. So that's messing with me.
I'm draining this coming Monday, so not urgent... just curious mostly about the TA info if anyone has any insight.