Alkalinity keeps dropping in Bromine hot tub

[jandersen13]

Hey everyone - hoping you can help me out here. I've been using the bromine method (3 step) listed in the sticky here but have been having trouble keeping TA and pH in line. For awhile TA was stable and pH was slowly creeping up. No problem and I would add dry acid every once in a while. But now it seems that TA is dropping and not stable at all. What could be causing it to drop? Is it the adding of bromine tabs in the floater? If so, do I just need to monitor and add baking soda to keep TA in line? I was expecting that TA would stay stable and then just dry acid every once in a while to bring down pH.

Also, my floater is just a cheap one with the twist adjuster and 2 holes in the bottom. I fully close the twister adjuster as the water comes in from the bottom holes and seems to dissolve the bromine tabs fairly quickly (add 2 or 3 tabs every 5 or 6 days). Is there a better floater I should look to get instead?

 

[JoyfulNoise]

Brominating tablets are acidic, they will cause the TA to decrease over time. You will need to adjust your TA up with baking soda and find a point at which the pH stabilizes but doesn't get too high fro aeration. It's a tricky balance and the tablet floaters are not very useful for metering the bromine. They seem to dissolve at high rate no matter what the opening setting is.

If you are set on using bromine, then you might do away with tablets and save them for when you have to go away on vacation. Instead, use the the sodium bromide / bleach method to maintain your tub's sanitizer. You simply add enough NaBr to create a bromide bank of about 30-50ppm and then activate the bromide (oxidize it into bromine) using bleach or liquid chlorine. It requires more day to day testing and additions but you will not have to worry about pH/TA crashing from acidic sanitizing tablets.

 

[jandersen13]

Thanks for the reply! Still trying to figure out my best options with my daily routines. I did end up adding baking soda the other day and that helped and got it within range (70 - 80 TA), pH was in range as well about 7.6 or 7.8. I forgot to check the floater for a few days and measure Bromine amount (maybe 4 days, schedule wasn't great), and the tub was a bit cloudy. I added tabs back to the floater (3) and then added 4 oz liquid chlorine. This brought the levels back up, but the water is still a bit cloudy (will be 24 hours when I get home tonight and will check if it's improved). I also switched out for a clean filter. But when the jets are on now, I did not a lot of foam, but before it was not doing that. The only new things that have happened are the addition of baking soda and the bromine going to zero for a bit. Any thoughts / advice? Also, should that cloudy water clear back up after running through the filter for 24 hours?

 

[jseyfert3]

My experience with cloudy water, and that of the forum in general from what I’ve seen, is that cloudy water is due to a lack of sanitizer. I run chlorine, and the only time I’ve gotten cloudy water is when it dropped to zero for a while. Stuff grows really quick in a hot tub with insufficient sanitizer, and cloudy water is an indication of this.

In my experience, it’s best to just dump and refill if this happens. You can clear it up with sufficient sanitizer over time, but it’s not worth the effort vs a refill. Filters will not clear up cloudy water.