Bromine -> Chlorine Conversion Question

[bedelliott]

Hello,
I inherited a spa along with a partial bottle of bromine granules - I used those up and now want to switch to chlorine/bleach since that's how I manage my pool. When the bromine granules ran out I let the spa start to go green then, thinking that meant most/all of the bromine was gone, I added my bleach. The bleach cleared up the green and I can smell it (I took the spa to 8ppm as somewhat of a shock treatment) but when I test the water the chlorine doesn't register at all, so something must be going on chemically to prevent the chlorine from showing up on my test, maybe there's still some bromine in there and would that cause this?
Anyway, I can drain & refill if need be, but I wonder why that's necessary - can't I just start the bleach route and maybe once the bromine completely disappears this chlorine will start showing up in my test? Has anyone dealt with this kind of thing?

 

[mknauss]

Once you added the bromine, the pool water became a bromine pool. The chlorine you added activates the bromine. You will not be able to test for the FC level. You need to drain and refill the spa to eliminate the bromine from the system so you can use bleach.

 

[bedelliott]

Once you added the bromine, the pool water became a bromine pool. The chlorine you added activates the bromine. You will not be able to test for the FC level. You need to drain and refill the spa to eliminate the bromine from the system so you can use bleach.

Thanks you, but I'm a little confused. Didn't my spa go green because it was out of bromine, just like my pool goes green when it's out of chlorine? How did adding chlorine activate bromine? I'm also curious why all the bromine won't get used up over some period of time, and then the chlorine would be all that's in there & start showing up on the test...? This chlorine is working, it un-greened my spa, or so it seems...?

 

[mknauss]

Sodium Bromide - Further Reading

www.troublefreepool.com

 

[bedelliott]

Sodium Bromide - Further Reading

www.troublefreepool.com

Interesting, that was a great education, thank you! I'll drain....

 

[bedelliott]

Interesting, that was a great education, thank you! I'll drain....

One more question if you don't mind... I'll be manually dosing my (10%) bleach - with a 101-102 degree spa do people typically have to dose 2x/wk to keep the FC up? (I was having to add the bromine 2x/wk)

 

[mknauss]

Based on testing and use. Many here use a swcg for the maintenance of their FC level.

 

[JoeSelf]

Your going to have to figure out your loses when not in use. But you should add after every use to eliminate the bather waste. Testing will help you figure out what you need to add.

 

[Gebo]

I use 10% and I use 1 oz/person after every use with temp at 103. This appears to be working for me.

I check my FC 5 days a week minimum. Every morning if we used it the night before.

 

[bedelliott]

I use 10% and I use 1 oz/person after every use with temp at 103. This appears to be working for me.

I check my FC 5 days a week minimum. Every morning if we used it the night before.

Thank you, very helpful. What's the FC consumption if no one uses the spa for a few days, have you ever gauged that?

 

[Gebo]

Thank you, very helpful. What's the FC consumption if no one uses the spa for a few days, have you ever gauged that?

Lol, we’ve never gone more than 1 consecutive night not using it. And that was only due to tornado like rain and wind.

We “always” go right before bed so that keeps us pretty consistent.

 

[Mdragger88]

Every spa will be a little bit different in regards to standby fc loss but it’s not a negligible amount so frequent testing is key.
To prevent excess fc demand right out of the gate you should do an Ahhsome purge before draining to remove any biofilms. This is a regular maintenance procedure that should be done every 3-6 months when its time for a water exchange anyway.
It is especially important if you have never done it or if you’ve run into a zero sanitizer situation.
The first purge may take many rounds to come out clean (the same water & just a 1/2 dose is sufficient for subsequent rounds).

what is ahh-some?

What is Ahh-some?

www.google.com

Here’s the chlorine spa guide

How do I use Chlorine in my Spa (or pool)?

If you have a question about any information within this Sticky, please start a new thread for yourself where you will receive very quick responses to your specific questions. Thank you! Introduction There are two main things to consider when maintaining your hot tub water, Water Balance and...

www.google.com

 

[bedelliott]

I haven't done the drain yet, I'm thinking I'll be sticking with bromine granular, so I've been adding some 10% bleach each day to carry me along until my bromine shows up on Sunday. I've noticed that, regardless of how much 10% bleach I add to my bromine spa, it does keep it from going green, but it doesn't make it crystal clear like the bromine-only approach was doing. Does this make sense? I'm wondering I've now hosed up my spa and need to drain & start fresh with bromine, or if I can go back to bromine with this same water and it'll go back to being perfect.
Also, regarding the dosing, I was adding 1 cap full of granular (maybe 1-1.5 tablespoons?) twice each week and that kept it crystal clear, but most on this forum seem to add a lot more & more frequently than that, at least when using bleach. Or does bromine just take a lot less than when you use bleach?
Lastly, I suspect my parents (who I inherited this from) never used ahhsome and the spa has definitely gone a bit green a couple times, but I'm curious if ahhsome is commonly known and being effective or if it's more of a marketing/gimmicky thing? Like why was my 2-3 tablespoons of bromine keeping it crystal clear if it's likely full of biofilm?
Anyway, thanks so so much for the education, I really appreciate it!

 

[newdude]

Like why was my 2-3 tablespoons of bromine keeping it crystal clear if it's likely full of biofilm?

The bromine was treating the water. The ahhsome treats the pipes. The little bit the pipes affect the water may or may not be noticeable, but they can still be gross.

Tubs get tested at the factory and they don't drain them out properly. It takes the residual plumbing water next to no time to go stagnant and it's arteries are already gross a short time later at delivery. It only gets worse from there. There's tons of purge threads if you search and you'll see for yourself what came out. You'll likely clean similar from yours. Mine sure did, and then some. It took 10 consecutive purges for it to run clear.

 

[Gebo]

I’m no expert by any stretch of the imagination but I would do an AhhSome purge, drain and refill. I couldn’t believe the gunk that came out of my brand new tub. I cycled it 6 times and even let it sit overnight.

I’m of the belief that fresh water cures many evils.

 

[bedelliott]

The bromine was treating the water. The ahhsome treats the pipes. The little bit the pipes affect the water may or may not be noticeable, but they can still be gross.

Tubs get tested at the factory and they don't drain them out properly. It takes the residual plumbing water next to no time to go stagnant and it's arteries are already gross a short time later at delivery. It only gets worse from there. There's tons of purge threads if you search and you'll see for yourself what came out. You'll likely clean similar from yours. Mine sure did, and then some. It took 10 consecutive purges for it to run clear.

How many ounces of the product did you use on each cleaning cycle? On Amazon it says a 2 ounce package does four cleans, meaning it takes a half ounce per clean, but I see posts where people are using 4 ounces per clean. My tub is about 500 gallons.

 

[Gebo]

It comes in a gel and a liquid. You’d need 4 tsp of the gel for a 500 gallon hot tub. 1 tsp/125 gal

 

[newdude]

+1 and for multiple purges you keep the old water and add a half dose for the next round. I was only using a tsp or 2 for most of the purges with a small tub.

 

[Mdragger88]

I don’t think you’re understanding how bromine works.
Not sure exactly what bromide product you were using but it was certainly some sort of sodium bromide.
At any rate you added the sodium bromide to the tub & it then requires activation by an oxidizer (dichlor, bleach,mps) to become bromine.
The bromide never leaves the tub unless you replace the water- it simply needs to be reactivated.
Many sodium bromide granules on the market are mix of sodium bromide & dichlor.
Have a read at the bromine guide to get a better understanding of how to properly sanitize your spa with bromine.

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

Originally Posted by waterbear There is a lot of misinformation on the proper way to use Bromine so I hope this primer is helpful. First, you need to establish a bromide reserve in the water. Bromine tablets can do it by themselves but it can take literally weeks until enough dissolves. Some...

www.google.com

 

[bedelliott]

I don’t think you’re understanding how bromine works.
Not sure exactly what bromide product you were using but it was certainly some sort of sodium bromide.
At any rate you added the sodium bromide to the tub & it then requires activation by an oxidizer (dichlor, bleach,mps) to become bromine.
The bromide never leaves the tub unless you replace the water- it simply needs to be reactivated.
Many sodium bromide granules on the market are mix of sodium bromide & dichlor.
Have a read at the bromine guide to get a better understanding of how to properly sanitize your spa with bromine.

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

Originally Posted by waterbear There is a lot of misinformation on the proper way to use Bromine so I hope this primer is helpful. First, you need to establish a bromide reserve in the water. Bromine tablets can do it by themselves but it can take literally weeks until enough dissolves. Some...

www.google.com

Very true that I don't understand bromine, all I know is sodium hypochlorite given the pool I've manainted for many years. I believe the bromine/ide product I inherited with the spa was a mix of ingredients like say, because that's all they ever used in the spa. The other day I decided to stick with bromine so I ordered SpaGuard's Brominating Concentrate which appears to have the sodium bromide/dichlor mix like you say, this seems easiest to me. The spa owners before me put in 1 capfuls of the bromide/dichlor product twice/wk and always had a clear spa, and they never even messed with pH/CYA/TA or anything else, they also drained every 6 months - seems like a very easy, minimalist approach. I'll read thru that guide you sent a link for, thank you!