Total Hardness Too Low after using SpaBoss PH Stable

[Hot Tubber in Ontario]

I recently emptied and refilled our hot tub and decided to use SpaBoss PH Stable for the first time. In the past our PH has bounced around and this product says it helps with that so I thought I'd give the product a try. I used it per the instructions on refilling it. After the product had been in the hot tub for more than 24 hours I tested it and found the hardness was too low so I added SpaBoss Cal-Rise. It turned the water cloudy (which the PH Stable instructions said could happen) and I kept rinsing the filter, after 12 or so hours the cloudiness went away. After I was left with a film/grit on the inside of the hot tub (also had residual calcium flakes on the bottom of the tub which I scooped out). I keep wiping it down with a rag and rinsing the filter. Now, one week later I just did the weekly shock and tested the water - hardness level is still too low, I suspect adding Cal-Rise will result the same as it did a week ago with cloudy water, flakes at the bottom, etc. What should I do?