Thanks for your help! I will definitely add a little at a time since it sounds like a pain if your levels get too high.

They did use a chlorine puck or two in the skimmer initially, but I used Ben's test kit and there was no CYA registering. I will test again before adding any, just in case.

So, from the way it sounds the CYA comes only in powder form since it has to dissolve? Wow, 7-8 lbs. sounds like a lot. I had no idea I'd need that much!

I had my hands on a small canister (I think the brand was Aqua Chem) in Walmart the other night. I almost bought it but decided to check here first since I wasn't sure if CYA was the same, regardless of the brand. Do they have better products at the pool store, or is it all the same?

Sorry for all of the questions... I'm slowly learning.