New To The Bromine Bank Concept

[hitmanx]

Hello,

I picked up a new hot tub with the basic knowlege of water chemistry but ignornace is easy to obtain... I'm having trouble getting the bromine system to work...

250 gallon

Foam walled insulated vinyl spa

Temp at 95 to 101

Bather load of 2 adults and 2 small children for 20min/day

Dec 23rd

Hot tub filled (thought it was soft but ended up being hard like 800+ppm out of tap, pH 8.2)

Quik stix test strips (came with chemical kit)

Spa-pure bromine pucks in floater on level 2

Added 50ml of mps shock

Alk too high

No bromine reading

PH high

Dec 24th

Found these forums and read until my eyes started to bleed... Going to use the 3 step bromine system with mps shock to start...

Dec 25th

Finally got TA to somewhere around 100 to 120ppm with pH down and aerated to bring pH up to 7.4 (test with aquarium drops)

couldn't find source of sodium bromide...

Dec 27th

Continued search for NaBr and finally found Brilliance Spa-start at walmart which apparently is NaBr but it doesn't list the concentration... It says use 60grams for up to 1900L but I used the 1/2oz per 100gallon amount which gave me 1.25oz but I didn't have a scale and it was late and i was frustrated so I used the density of NaBr (3.21g/cm³) to calculate 13.24ml and used that to decide to add 1tbsp of the start-up then added about 50ml of shock and left cover off for and hour and tested.

1-3ppm of bromine!!

Dec 28

No bromine residual with test strips

Bathed with family anyways during first snowfall of year! Was so nice, but getting out was torture!

Added 25ml of mps shock

Uncovered for 1hr

Maybe 1ppm bromine

TA good

PH good after 15min aeration

CH 800+

What gives?

I have a Taylor 2106 on its way and a digital scale too so I can be more accurate, but did the brilliance spa- start give me enough of a bromine bank? Or has the bather load actual contaminated the tub so much that the bromine is having trouble keeping up with the established nasties?

Thanks, I am glad I found this site.

Nigel

[chem geek]

The density of granular products is not nearly as dense as solid which is what you looked up. 1900 liters is 500 gallons. 60 grams would be 2 ounces weight if the density were 1 g/ml which is a typical bulk density for granular products. However, Brilliance for Spas Brominating Granular according to this MSDS is 85% Dichlor and 15% sodium bromide. So it isn't good for creating a bromide bank. There are LOTS of products for sodium bromide -- some of them from poolgeek.com (and available in some spa stores) with 99% sodium bromide are as follows:

SeaKlear Spa Sodium Bromide

Rendezvoud Broma-Start

Leisure Time Sodium Bromide

Natural Chemistry Spa Bromine Start

Once you create a larger bromide bank you can see if you can create more bromine more readily, but it may just be that you aren't adding enough oxidizer to create enough bromine given your bather load. A new hot tub can have a higher oxidizer demand with greases or biofilm. It's a good idea to use Ahh-Some so before you change your water on your next refill I suggest you use this product.

[hitmanx]

Thanks for the reply but that isn't the product that I used. It's not the regular bromine granular, but a product called startup. It's designed to make the bromine bank but like I said it doesn't list the concentration and I couldn't find the msds for it. Where did you find it for the granular?

I haven't been able to hit some of the local pool shops because of holiday closures and out of all the box stores only Walmart sold anything mentioning sodium bromide. Trust me I would love to just walk into a store and buy a bucket of pure sodium bromide. But finding a Canadian source online is proving difficult.

That ahhhsome product is a cleaner before I make my next water change?

Thanks again.

Edit: I just found a local spa store that has liquid sodium bromide with 32% but nothing else listed. The nice lady said they use it as a generator to start up hot tubs for bromine with pucks.

Another edit: I just got off the phone with a nice man named Dewy at Brilliance for spas and he told me that the start-up is 95% sodium bromide and he's sending me the msds to confirm...

So if I added 1tbsp of 95% NaBr to 250 gallons should I have enough of a bromine bank? Are there already too many nasties growing to keep up? Are my test kits bunk? The shock I'm using says add 11g weekly and 22g at start up and because I don't have a scale yet (coming in mail with my Taylor 2106) I guessed roughly based on the equal weight of tablespoon of sugar weighing 12g but all this silliness is not very accurate

[hitmanx]

For reference...

Brilliance in Spas Start-up

SECTION 3.

COMPOSITION/INFORMATION ON INGREDIENTS

CAS OR CHEMICAL NAME SODIUM BROMIDE (NABR)

CAS # 7647-15-6

% RANGE 95 - 100

[chem geek]

The normal sodium bromide startup dose is 1/2 ounce (1 tablespoon) per 100 gallons. So for 250 gallons that would be 2.5 tablespoons. So what you added was low. Nevertheless, you should still be able to produce up to 11 ppm bromine or so. So I think the issue is more that you just had a high bromine demand. Nevertheless, you can always add more sodium bromide to get up to where you should initially.

For most granular products, 1 teaspoon weighs roughly 5 grams and a tablespoon is roughly 15 grams. Your sugar is probably finer than most granular products so is less dense (more interstitial space).

Just add enough oxidizer to keep your bromine level from getting to zero and you should do OK.

[hitmanx]

My scale arrived and I weighed the amount that I added the other day and it was only 1.15oz so I added another 0.1oz to bring it up to the correct amount for 250 gallons, then I added 11g of shock and circulated for 30min... I checked bromine residual with test strips and I finally got a decent reading of 3+ppm

Can I add too much bromide? Upon further reading, the start-up product says to add 2oz to pretty much all size Spas...

I shocked again after a long soak last night, but I'm gonna test again today to see if there are proper residuals as I have the floater fully open too.

Thanks for your input. Hopefully all remaining questions will be answered with the Taylor 2106 that arrives tomorrow.

[chem geek]

You can't add too much bromide (well, assuming you aren't adding thousands of ppm of it). In fact, when you add brominating concentrate and especially when you are using bromine tabs, you are adding more bromine to the water that when used/consumed will become bromide. So the bromide level will increase over time.

The only side effect of this would be if you have an ozonator since the higher bromide level can lead to having a higher bromine level when the ozone oxidizes the bromine, though the effect is fairly small since even with the recommended startup bromide level much of the ozone will convert bromide to bromine before the ozone itself breaks down.

[hitmanx]

I wasn't getting proper residuals the last two days even though the floater was half open, so I ended up shocking again and then also adding another 0.75oz of sodium bromide like the bottle says (total of 2oz)... I shocked again and left the tub to sit for a day...

Still using test strips, but as of this morning the bromine was 3-5ppm... The family went in today so I will check the bromine again tonight.

I have heard of people shocking after each session, but the bottle says to shock once a week... Its hard to find a balance it seems... With mps shock I have read that it builds up other substances over time requiring water changes more often. Obviously I'd like to minimize the hassle of shocking and just try to maintain the residuals with the pucks. What is considered a high bather load?

[chem geek]

The bottle is wrong. Unless you have a low bather load with short soaks, it is unlikely that your bromine floater will be able to output enough bromine to handle your bather waste. The bromine tabs in the floater are designed to provide a background dose of bromine in between soaks. To handle your bather load, you need to add an oxidizer after every soak, not once a week. As for what is a low vs. high bather load, it's up to you -- if you are able to output enough bromine from tabs in a floater to always maintain a residual, then you have a low enough bather load to have tabs alone handle that demand. I doubt that is the case, but again you determine that for yourself in your spa.

MPS builds up sulfates, but in a spa those should not be a problem the way they would be in a plaster pool where high sulfates are bad for concrete.

[hitmanx]

Yes this is all starting to make sense. If my Taylor kit would ever get here I could have a better handle on this situation. Im not sure i am at the right ph as the colours are so close on the strips and my CH is 800+ so i need to figure that one out too before my heater and pump blow up.

I will start shocking after each soak and using the floater for background. Is there a preferred time for the shocking to work uncovered when using mps vs bleach?

Also up here in Canada I can only find regular bleach which doesn't have % listed, and disinfectant bleach which is 7.5% and ultra that is 8.25%. So given these numbers I can work out my dose if i knew how much total ppm i needed for shock.

Thanks again.

[hitmanx]

I finally received the Taylor kit...

I shocked the spa and tested an hour later

Using the test strips first the bromine was very dark, like 10+ ppm, so I verified with the new kit... It took 28 drops at 25ml sample, so the bromine was 14ppm! Whoooooo!

TA 80ppm

Ph 7.4

CH 300ppm

Then I tested again 24hrs later and the bromine is still 11ppm... I really was hoping to take a soak as I haven't used the spa in a couple days. Should the residual really be so high? The spa was uncovered for a couple hours yesterday and then covered again...

[chem geek]

If you got the bromine up high then it can take a while to drop if there is no bather load. That's not a bad thing. You can use a chlorine/bromine reducer (usually sodium thiosulfate) if you want to lower it faster, but in the future don't raise it so high to begin with.

[hitmanx]

And I raised it too high because I used too much mps vs the smaller bather load this week?

[chem geek]

Yes, that is correct. You need to scale your oxidizer dosage after your soak in proportion to the bather load (number of people soaking for how long).

[niomim]

hello my eyes are bleeding too i have purchased a hot tub it’s 806L i have been using bromine granules but can not get a stable level its either too high or non existent and gone with the building a bromine bank option, i have purchased sodium bromide @ 99%, i have non chlorine shock (mps) and also now purchased bromine tablets and a floater, after endless hours trying to figure out the bromide bank i found i need 56.7g/2oz per 1900L/500Gal so if i have  calculated correctly i will need around 25g (56.7/1900x806) to build my bromine bank followed by my shock, this is where i’m getting confused as seems i need 30ppm in my bromide bank but obviously the bromine levels should be 3-5ppm i don’t want my bromine ppm through the roof and not been able to use my spa for days so could someone advise how much sodium bromide i should add for a ppm of 5ppm so i can use and maintain this level thank you so much 🤯

[RDspaguy]

@dlleno, this one is for you, bud.

[dlleno]

you should consider the "ppm level of your bromine bank" separately from actual bromine levels.  if you have a large enough bank (label directions) then you can forget the tablets and floaters and just use regular dichlor just like the chlorine guys do.  

if you know how  to calculate the amount of dichlor that will produce 3ppm of chlorine in a chlorine aps -- just use that same amount.  the bromide bank will do the magic and produce the correspondingly safe level of bromine.