Not sure how to adjust FC levels with tablets

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dooger54 said:
Ok. Will give it a shot. How do I know if my Bromine “bank” is adequate?
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There’s no simple and definitive method since the test reagents you have behave the same with chlorine & bromine but here’s a way to give you a good feeling for it -

Start off with your spa in an unused state. Remove any bromine tablets in the feeder. Use the Pool Math calculator to determine how much bleach or dichlor it takes to raise your FC to 10ppm, that corresponds to 20ppm bromine. Add the amount of chlorine with the jets off but the tub circulation on and wait an hour. Retest the water and, if your total bromine measures 20ppm, then you’ve probably got a sufficient amount of bromine in the tub. If you do not measure 20ppm, then you could either not have enough bromide in the water or you have organics in your tub creating a high enough sanitizer demand that it’s skewing the results. Like I said, it’s not easy.

When you do your next tub fill, you should follow the process outlined in the sticky for how to use bromine in a hot tub -

How do I use Bromine in my spa (or pool)?

By using sodium bromide to establish the bromide bank, you know for sure how much bromine is in the tub. Tablets are a nice convenience to have for when you can’t be around the tub for daily maintenance but they are not a good long-term use strategy.
 
dooger54 said:
Started today doing what you recommended. For the first time ever I am now getting a large amount of foam when the jets are on. What’s happened?
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Did you use liquid chlorine bleach to raise the bromine levels? Is the foam persistent after the jets turned off? How old is this tub? Has the tub’s plumbing ever been purged using Ahh-some?
 
JoyfulNoise said:
Did you use liquid chlorine bleach to raise the bromine levels? Is the foam persistent after the jets turned off? How old is this tub? Has the tub’s plumbing ever been purged using Ahh-some?
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Using liquid bleach, low splash variety from HD. Just checked tub this morning, no foam now. Tub is 11 years old. I have cleaned the plumbing, used Spa Purge from Leslie’s. Did it last winter. We are snow birds, so the tub is only used Jan-April.
I have some Ahh-some in order.

Just checked levels. Ph high again, about 8. TA low at around 30. Will work on that. Have not checked bromine level yet. I did order some R-0872 also.
 
low splash variety from HD
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Do not use that bleach! It has polymers/surfactants that is making your spa foam. Only PLAIN bleach. Best place to get it is Walmart or grocery stores.
Home Depot/Lowes bleach/liquid chlorine is typically old and degraded. They do not get the turnover that a Walmart or grocery store does.

Just be sure it is plain. No scents, splash less, etc. And no Cloromax by Clorox, it has polymers too ---

Take care.
 
Thanks Marty!!

Yup, the low splash bleaches cause foaming issues. The polymers used to create the greater viscosity are very hard to break down with chlorine. If the foaminess persists, you might have to dump the tub water.

If you read through the TFP Pool School, there’s a discussion of what chemicals to use in pools and hot tubs and what types of chlorine products are best.
 
Since you are planning on coming off of acidic forms of sanitizers (tablets and MPS), your pH rise is going to be more dramatic. I would suggest you adjust your TA up to 50ppm and then consider adding 50ppm borates to your hot tub. Borates will act as an additional pH buffer where their greatest buffering capacity is at high pH. This will slow the rise of pH from CO2 outgassing caused by the air jets. The downside to adding another buffer to your water is that adjusting the pH will require a larger amount of acid BUT, because the pH rise will be slowed, the total amount of acid used over time is the same. There are stickies on the forum on how to add borates to your water. I find using boric acid the easiest method and my swimming pool always has 50ppm borates in it. Borates will also soften the water and give it a "silkier" feel. Because borates keep the pH from getting too high, calcium scaling is also less likely and that is the main culprit in hot tub heater failures.

Its up to you but you should be aware of the pH issues you're going to run into.
 
JoyfulNoise said:
Since you are planning on coming off of acidic forms of sanitizers (tablets and MPS), your pH rise is going to be more dramatic. I would suggest you adjust your TA up to 50ppm and then consider adding 50ppm borates to your hot tub. Borates will act as an additional pH buffer where their greatest buffering capacity is at high pH. This will slow the rise of pH from CO2 outgassing caused by the air jets. The downside to adding another buffer to your water is that adjusting the pH will require a larger amount of acid BUT, because the pH rise will be slowed, the total amount of acid used over time is the same. There are stickies on the forum on how to add borates to your water. I find using boric acid the easiest method and my swimming pool always has 50ppm borates in it. Borates will also soften the water and give it a "silkier" feel. Because borates keep the pH from getting too high, calcium scaling is also less likely and that is the main culprit in hot tub heater failures.

Its up to you but you should be aware of the pH issues you're going to run into.
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I am going to drain and start over. After using that bleach I cannot get the tub to stop foaming. Waiting for my Ah..Some to come in the mail. I also got some Gentle Spa (per recommendation s here) and will add that.
 

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Tablets are good for when you can’t dose the tub with chlorine every day. It’s like using stabilized chlorine pucks (trichlor) in a pool - they have a useful role in pool care but not for continuos long term use.
 
So I got my Ahh..Some, cleaned and refilled my hot tub. Pretty much followed the directions in the “How to use Bromine in your spa” sticky. Added the recommended amount of sodium bromide, currently adjusting TA and Ph levels. I will not use the Bromine tab feeder for now. Will add a cup of chlorine bleach once a week as instructed.

Do I need to add some bleach after every use? Or once a day? Not sure how to “maintain” now that I won’t use the feeder tabs. My tub is 250 gallons.
 
You need to add chlorine in after every soak because you need to make sure there is sufficient oxidizer around to destroy bather waste. If you plan to use the tub every day, then you want to add enough chlorine after a soak so that your bromine level is between 2-4ppm when you want to soak again. It's a little bit of trial and error but there is a rule of thumb for hot tubs in this post - Help a spa

So give that a try and see how your bromine levels go. In the beginning with a new tub, you'll probably test and dose every day until you get to know how your tub is responding. Once people get to that point, then they're usually dosing the water without doing a lot of testing as they simply know what to expect.
 
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