I need to bring my ph down to 7.2 and maintain it for a while to help in removing a stain using Jack's Blue Stuff. In testing for the stain, I needed he Copper & Scale stuff to remove he stain....problem is that I can not bypass the heater. According ot Jack's, I can use the Blue Stuff over a period of time and it should reduce the stain. My challenge is this....my Alk is currently about 70 and my ph is about 7.5. If I add acid, my Alk will also reduce....If I add baking soda, my Ph will increase. Which should I work on first?