I'm new here. I've really learned a lot reading some of the posts here, and love how people answer questions so nicely here. Awesome community.
We opened a new AG ~4400 gallon Intex pool late this season -- around 8/14. I went to the closest pool store for help with free tests, and getting levels right. All they really asked me to do was raise my TA (which I went and did with baking soda) and CYA that I bought from them. They sold me a BioGuard starter kit, and I used their super soluble for a while until I read about BBB. Then I bought a couple bottles of 6% bleach, and have been testing and adjusting the Cl every day or two. No big problems. The last time I had them test it, they said my TA was 108, and I ought to adjust it by adding more Stabilizer 100 (read: baking soda). I had a previous test say it fine, and my test strip readings are around 150 anyway, so I thought I'd just ignore that reading for now, and try later.
Looking for a solar cover they didn't carry, I went to a more remote pool store, and brought them a water sample while I was at it. All their readings were different from what I expected. From what I've read, CYA and TA don't wander far unless one is dumping chemicals in, so I was surprised. Pool store 1 said CYA was 34, 2 said it was 15. Pool Store 1 said TA was 108. 2 said it was 218. 218!? I had them test it two more times... once with a different packet of whatever they were using. Same dark green.
These tests were only about a week apart. Both the CYA and baking soda were added over a week before either test. I run the filter for a while before taking samples, and take them a foot or two down. The other thing worth noting is that the first pool store thinks TA belongs between 125-150, and the second thinks it should be 60 to 100. Not sure why. My first batch of Bioguard test strips thought it was 150 (which is what I figured I was targetting with my baking soda doses anyway). I'd say the second batch (PoolMaster) might have been more like 170 today. I'm not so surprised test strips can vary like that. Based on the amount of baking soda pool store 1 said I should add, (8.5 lbs to a 4400 gal pool reading 30 at the time), I was expecting to be upwards of 150, and the strips don't seem far from it.
So I have one pool store trying to have me raise the TA. The other wants me to lower it. A lot. I now notice that even 150 is rather high by most standards, if that's what I've really got, so I'm not sure what pool store 1 was up to.
There's so little of the season left, I'm not sure I'm even up for buying a lot of chemicals. I was planning on draining the pool in late september or early october (we're in Pacific NW -- I may be being optimistic here)
I suspect the answer is: "Get your own test kit and quit fooling with these clowns." I was planning on doing that for next season, and just getting by with test strips and pool stores for this month or two. Any other insights?