Is it normal for TA to increase after you've increased your Borates from 0ppm to 49ppm (13 boxes (988 oz) in 17,100 gallons pool) and then add enough muriatic acid (4 gallons) to bring pH back to 7.5? I started with 140ppm TA and now it is 200ppm.
Using pool math, I thought that the TA was going to rise 113ppm from adding 13 boxes of 20 Mule Team Borax and decrease 117ppm from adding 512 ounces of 31% muriatic acid.
If the TA increase is abnormal, do you guys think that adding the Borax in the skimmer "cleaned" my sand which released TA that was somehow clinging to my sand? I have had scaling a few years back that may have affected my sand in the past, but it's been cleaning well. I didn't add acid through the skimmer, I added one gallon in front of the return jet after every 3 boxes of Borax through the skimmer.
The water feels "sticky" when I rub my fingers together now while it didn't in the past. I verified this is a side effect of high TA.
I know I need to add muriatic acid and aerate, I just wondered if others had this problem before.