I've had my bromine-based tub for about a two weeks and since getting the pH, TA, CH, and bromine in line, I've had daily pH rises that I am unable to stop. I had 2 different kinds of test strips + a phenol red kit - typically the drops are showing a higher pH than the strips; in fact, often times the drops will show red/8.2+ (filling to the fill line + adding 4 drops + inverting as per the instructions) and the strips will show somewhere in the mid to high 7s. I had my water tested yesterday and it came back as follows:
pH: 7.2
TA: 73
CH: 127
Total Bromine: 5
TDS: 700
They suggested adding 9.75 tablespoons of SpaGuard Balance Pak 100 to hit their suggested TA of 125-150. My manual suggests that 80-120 is acceptable. I added 4 tbsp of baking soda, which increased my TA (it looks like it is around 70 now after more reducer was added). Checking the hot tub this morning, the pH is once again showing 8.2+ using the phenol red and in the high 7s using the test strip. This has been a daily occurrence over the past week, save for yesterday when I added baking soda. I find the phenol red is all over the map - almost as though the red color if affecting the water color rather than the reaction - I tried two tests this morning, one was 8.2+ and the other was around 7.7 - difference was adding 2 drops and inverting then adding another 2 and inverting vs adding all 4 at once and inverting.
I've heard people of both sides of the fence - get your TA in line and then adjust your pH vs. a low TA (60+) is fine, just control your pH. I do have an ozonator and noticed a decent amount of bubbles coming from the other jets when the filter runs. Could this be enough the be raising my pH daily? Should I try to spike my alkalinity by putting in ~10 tablespoons of baking soda + aerate? This will undoubtedly raise my pH, which could be brought down by using my pH reducer (using Aquarius pH Reducer - granular from Canadian Tire), but I'd rather not add a pile of both substances if it is not necessary. Or am I doomed to needing to add pH reducer on a daily basis?