A CYA of 50 is fine...just keep your chlorine at 5 or above, and you should have no problem at all. I don't know if you close your pool for winter or not--if you do, you'll lose some of the CYA when preparing it for winter. If not, (I don't), you'll likely see the CYA fall due to dilution (and the unexplained phenomenon of CYA dropping over the winter that some people on this forum, but not others, have experienced). Then you can run it back up to wherever you want it. Personally, in your climate, I would think 50 is idea anyway. (Then again I run mine around 80 intentionally and most people think I'm nuts! )

Janet