If you don't want to use the dichlor, it is perfectly fine to use the granular CYA. I have done so for many years without a problem. You can slowly pour it into the skimmer while the pump is running and then just leave your pump running for the first 4 or 5 days after adding it while it is dissolving. Don't retest your CYA level for about a week after you add it to make sure it is fully dissolved and in the water to be able to be detected or else you are just wasting your reagent.