Good morning again! I see you did a few posts.

To address your most recent test results:
- With your low CYA of 50 for someone with an SWG, yes, you will need to add a little stabilizer. About 15 ounces should do it. Soak the stabilizer in an old white sock near a return jet. It takes a few days to increase on testing.
- Assuming then your CYA will be 70, your FC should be "5". About 2 cups of "regular/plain" bleach can get you there quickly until your SWG is adjusted to stay a little higher
- Your pH and TA are just fine
- Your Th (we call it "CH") for hardness is fine for an AG vinyl pools.
So other than some fine-tuning on your CYA and FC, you are in pretty good shape - according to THOSE results. I say that because I must caution you that those HTH 6-way strips have their limitations. I would still encourage you to order a TF-100 or Taylor K-2006 test kit from
TFTestkits.net. It's ways possible that one or more of the readings you're getting from the strips is off which would cause you to consider adding the wrong amount of something.
As for the scaling, that's normally something related to higher levels of CH, and yours appears to be low, but again, that' s from the 6-Way testing. I'm not so sure how reliable that is. Is your SWG very old? Your on well water, so I wonder if perhaps that has something to do with it. For now, continue with your small chemical adjustments and we'll see what other feedback we can get you on the SWG specifically.
- - - Updated - - -
Here are some previous discussions on how to clean a cell:
How to Properly Clean a Cell and
Cleaning SWG with CLR ? and
Cleaning Intex Swg system