new to pool stuff

I will definitely take it back. Price was ridiculous! I found granular 96% at Home Depot for MUCH less. Directions say to slowly add it to the skimmer & not backwash for 48 hrs.

The stuff is a slurry of the monosodium salt of cyanuric acid. Its advantage is that the CYA is available in the water as soon as it is mixed. Its disadvantage is that is is VERY expensive compared to CYA. I gallon will add about 35 ppm in 10k gallons of water for around $30 whereas 3 lbs of granular CYA will do the same for about $5/lb or less (about half the price). Whether it is worth it depends on how quickly you want the CYA in the water. You would need about 6 lbs of dichlor to add about the same amount of CYA and at about $5/lb or higher average price works out to be about the same as the liquid stabilizer. Advantage is you also get the chlorine (about 40 ppm in all when you add 6 lbs), disadvantage is that you cannot add the entire dose at one time.

As far as the granuular CYA. add it slowly to the skimmer, run your pump continuously for the next 24-48 hours, don't backwash for a week, and don't test the level for a week.
Also, the Taylor number for your leslies 81-330 is K-2005. Since you have added the FAS-DPD test you have teh equivalent of a K-2006. You might want to consider adding the OTO test kit for quick daily checks (Taylor K-1000 or Leslies 18554, they are the same) If you do be aware that the pH reagents is NOT the same one as the one in the bigger kit so don't mix them up!

Hope this helps.

I have added the granular cyanuric in a sock. Waiting for it to dissolve. What FC level should I be aiming for now? What CYA level eventually?

With no CYA in the water, make sure you keep your chlorine between 3-6 ppm at all times. (Now is when the best guess chlorine chart linked in my sig will become important to you :) ). However, as your CYA level rises, so must your minimum chlorine (use the chart!! ) We usually initially tell people to aim for 40-50 ppm of CYA to start with. However, I'm about 2 1/2 hours from you, so my climate is very much the same as yours, and I find that I lose too much chlorine too fast if I keep it that low. I run my pool at 80-90 ppm CYA, but it's in full sun all day.

My advice to you would be to start with about 50 ppm, test your chlorine use daily for a few days, and see what your average is. Then bump your CYA up by about 10-20 ppm and see if your chlorine use slows down. You can keep bumping up a little at a time this way until you find the point where you're losing the least amount of chlorine in a day. By only bumping up a little at at a time, you won't completely overshoot your idea level, because it's easy to lower the CYA by 10-20 ppm than it is to tell you right off the bat to go for 90 ppm.

There is NO good reason to put it in a sock with an ingrround pool unless you are still backwashing every day or two. Even in the sock much of it will go out and end up in the filter and if you backwash you will possibly lose some of it. In any case. forget about it for a week and then test the level. Whatever it tests at in a week is going to be it so if it is still to low then add more.

I guess I have been so accustomed to backwashing 2-3 or more times/ day that letting it go for several days scared me. But I see that the pressure is holding at 10-12 lbs. over "clean" pressure. (Last backwash was about 24 hrs. ago.) So maybe I should backwash once more & then add the cyanuric to the skimmer?

You want to be able to go 2 - 3 days without backwashing, before you add it to your skimmer.

It has been a week since I added 12 lbs. granulated cyanuric acid + 1 gal. liquid Instant Conditioner. The granulated has finally dissolved & my CYA=32 (dot finally disappeared). I am using about 2 lbs. Cal-hypo/day to keep the FC=3-5. pH is holding steady at pH=7.6-7.8. Other results: CC=0-.5, TA=125, CH=500.

Pool never looked better! Sparkling clean! Also, my filter only needs backwashing maybe once a week. What are your recommendations? Should I add more cyanuric?

You'll probably want the CYA closer to 50 to make it easier to keep chlorine in the pool. I'd quit using the cal-hypo. Your calcium hardness reading is getting pretty high and you may end up with some cloudy water issues. (Recommended level is 200-400 for a gunite pool. Vinyl pools don't need any.)

As watermom said, stop the cal hypo because your calcium level is pretty high. You might want to consider dropping the TA down a bit (around 80 ppm) so yo don't accidentally create scaling conditions if for some reason the pH should spike (it does happen).