I don't have a skimmer (I'm not even really sure what a skimmer is) but I did some searching and found the suggestions in several places to use a tube sock to dispense cyanuric acid. I put 10 oz. of granules in a tube sock and hung it over the side in front of the jet, with a weight on the ground outside the pool to keep it from falling in. So far it's about halfway dispersed.

Is it really necessary to test the CYA level? If its function is to keep chlorine from dissipating as quickly, can I use the rate of chlorine depletion as a general guide and not worry about testing the CYA specifically? I ask because stand-alone CYA tests seem to be hard to find and I'm not excited about buying a whole other test kit in addition to the one I already have.