How does your water look today? Yes, you can go ahead and start working to lower the alk. It is a gradual process so don't expect huge changes quickly.

I'll let someone else advise you where to buy CYA reagents but to answer your question, yes, you can buy bottles of it. In fact, you can buy much larger bottles of it than what comes in the kit.

While you are doing the online ordering of the CYA reagent, do yourself a big favor and go ahead and order a good test kit. We recommend the Taylor K-2006 or 2006C which is the same kit with larger bottles of some of the most used reagents. If you order through the Amazon link in my signature, the Pool Forum makes a little money on the sale which helps keep the forum up and running. Only buy if the seller is Amato Industries, however. Some other sellers are substituting the K-2005 which you do NOT want.

Regarding making duplicate posts -- don't worry about it if it does happen. One of us will just delete the extra one. Glad you found us and hope we are helping! You have a great day, too.