tggs,

Let's take an issue at a time and see if we can't get you going.

pH - I'm gonna' disregard that 15 (even the corrected >8.2) and assume your pH is somewhere around 7.6 - 7.8. please confirm that with another test. If so, you're okay for now.

Cl - This is where I think the biggest mix up is occuring. The shot glass method you are using is only applicable to an OTO test and that test measures TC ONLY. I'm not sure how you arrived at the FC and CC but I'm pretty sure those numbers are wrong. Describe your Chlorine test and we'll get that straight.

CYA - I agree completely with your first post....CYA is your primary issue and the reason your Cl reading goes to zero every day. Do not put in 3 lbs. Put in 1.25 lbs. You can get it at Lowe's, Home Depot, or the pool store. It will take a few days to dissolve so don't backwash.

Now, because your CYA will take a while to start protecting your Cl, your Cl will still drop to zero every day. I'd put in one of the .75 gal jugs of Clorox right at Sundown each evening for the next few days. Pretty soon, you'll be able to detect some TC in your pool even after a full day of Sun. That means your CYA is working. You should post up your numbers again at that point.

Keep reading everything you can on this forum. I also like this site for some good info: http://www.deh.enr.state.nc.us/ehs/chem.htm#ta

Stay the course......this will get easy.