How do you lower Alkalinity without raising pH in a spa?

Try a cup of Muratic acid. You can get it in a pool supply or hardware store. It will lower the PH but its a balancing act at best. if your water is a bit on the acid side it will be clearer and your chlorine will work better. I used to be very worried about such things as well but in time they wont seem to be all that important any more. Good Luck with your new hot tub