PH Drop With Bromine Floater Expected? How to Solve?

[mscdman]

When I am NOT using the bromine floater and only the bleach activation of bromide into bromine my PH seems to be stable at 80TA and 7.6.   

However, when I switch to the bromine floater and don’t use the tub for a day or two the PH will drop to 7.4 or 7.2.    Should I be running a higher TA with a bromine floater to reduce PH drop than with the bleach method?

[mscdman]

Anyone have thoughts?

[waterbear]

Bromine tablets are acidic and can cause a drop in pH if there is no aeration and the tub is covered so CO2 can't outgas. However, once the tub is uncovered and starts running pH usually rises quickly.  If it doesn't then your TA is too low.

How quickly does the pH rise when the tub is turned on and the cover off or does the pH stay at the same reading? As long as the pH is stable and is above 7.0 it's ok.

You can try bumping up the TA by 10 ppm and see what that does if the pH is constantly dropping and let it run for a few weeks. If it stabilizes you are done. If it's still dropping bump it up another 10 ppm until you find the sweet spot for YOUR tub. 

Remember, pH (and all other water parameters) are not constants and will go up and down. This is why it's good to check sanitizer and pH daily (or, at least, a few times a week) TA weekly to biweekly, and CH biweekly to monthly.

[mscdman]

PH rises quickly when aereation happens.  I guess I was trying to plan for management of PH when I’m not using the tub for a week or so

[waterbear]

IF you are not using the tub set the floater to only add enough sanitizer to maintain a minimum level since there is no bather load happening. This should slow down the pH drop. You can try bumping up the TA like I suggested and see what impact that has on pH stability, both with the tub unused and with use. As long as the pH stays below 8.0 you are good. Remember, bromine does not have the pH limitation of chlorine, especially in an unstabilized or understabilized chlorine tub.