Another Bromine Question

[Biggen]

Been using Frog @Ease with my new Hotspring for the past 4 months or so.  I like the system except for the cost.  I'm finding I'm exhausting cartridges about every 18 - 21 days which is not ideal.  I've been doing quite a bit of research on moving to a bromine sanitized spa.  I've read over the 3 step process and think I'm pretty familiar with what to do.  However, I do have a few questions.  

1. I understand I add sodium bromide to the spa on a fresh fill (or anytime coming from a chlorine spa but I will start fresh anyway).  Then I add oxidizer (called "shock") to the bromide to convert it to bromine which will raise bromine levels. My question here is "How much shock do I add"?  I have dichlor granules on hand.  If I want to raise the bromine level to ~10ppm starting from 0, then how do I know how much dichlor to add to a 350g tub in order to do that?  I guess I could add a teaspoon and test after a few minutes to see what the bromine level is.

2. I plan on using a floater with bromine tabs so I don't have to constantly add oxidizer on a daily basis.  I see I want to shoot for consistent 4 - 6ppm bromine levels.  I guess this is trial and error as far as how many pucks to use, what setting on the floater to select, and how long they last?

3. I understand I need to shock at least weekly and boost those bromine levels up to 10ppm+.  If using a floater, do I need to also shock after each soak or is weekly enough?  My tub also has a ozonator but it only runs when pump 1 is active and so it doesn't run 24/7. 

4. How long does it take from bromine levels to fall after a shock?  If I shock and raise the bromine levels to ~15ppm in the evening after we have finished with the tub for the night, will it be back to 4 - 6ppm by the next day?  I have done some reading in here and some people have commented it can take days to drop from 20ppm back to usable levels of 4 - 6ppm.

[waterbear]

20 minutes ago, Biggen said:

how do I know how much dichlor to add to a 350g tub in order to do that? 

.25 oz (by weight) per 100 gallons. 1 oz. or just under should be about right.

21 minutes ago, Biggen said:

.  I guess this is trial and error as far as how many pucks to use, what setting on the floater to select, and how long they last?

Yep, pretty much. I would get a Pentair 335 floater for 1" tabs because of it's adjustability and construction. Fill it about halfway and open it about an inch for start and see how well it maintains your bromine over the next week or two and adjust as needed. Much depends on how much use the spa gets. If the spa is going to be unused for a few weeks then close the floater down. If it is getting extra use then open it a bit more. You will soon develop a 'feel' for it.  (This floateralso comes in blue.)

 

33 minutes ago, Biggen said:

I understand I need to shock at least weekly and boost those bromine levels up to 10ppm+.

"Shockng" helps "burn off" organics in the water from users (body oils, sweat, traces of feces, urine, etc. that EVERY bather adds to the tub water no matter how clean they THINK they are). If the tub is not getting a lot of use then you can shock less often, If it's getting heavy use then shock more often. Once a week is good for most people.

37 minutes ago, Biggen said:

If using a floater, do I need to also shock after each soak or is weekly enough?

The whole idea of 3 step bromine is that you do not heed to add chlorine (or other oxidizer) after every use, unlike 2 step bromine (or chlorine--bleach/dichlor)

40 minutes ago, Biggen said:

How long does it take from bromine levels to fall after a shock? 

Depends on the orgainic load in the water, whether the tub is covered or uncovered, and whether it's circulating or the pumps are off. FIrst shock after fill can take longer becuase of no organic load in the water.

42 minutes ago, Biggen said:

f I shock and raise the bromine levels to ~15ppm in the evening after we have finished with the tub for the night, will it be back to 4 - 6ppm by the next day? 

You are not shocking every day and the tub just needs to be under 10 ppm before you go back in.

43 minutes ago, Biggen said:

I have done some reading in here and some people have commented it can take days to drop from 20ppm back to usable levels of 4 - 6ppm

There was a recent post to that effect but it was the first shock to activate the bromine bank after a fresh fill. Also every tub is different so what you experience is not what someone else will experience. The key is regular testing and keeping notes of test results and amounts of chemicals added and tub usage (normal, low, or high). This is how you will know what is working and what is not working for YOU.

Final bit of advice, stop worrying so my and enjoy the tub. It's something to help you relax, not stress over. There is no 'recipe' that works the same in every tub so just follow the guide, record your tests results and chemical additions, and soon you will have it down and realize how easy it is.

 

 

[Biggen]

I appreciate your help!

Ok, I think I have it pretty much figured out at this point in time with what I've read and what you responded with.  No just need to wait on a supplies I ordered (test kit, sodium bromide, etc...) and I can do a drain and fill and get using it.

[Davekro]

Biggen,

I am having similar questions about how fast my Bromine level will drop from 24 ppm after  adding the Sodium Bromide Reserve after fresh fill on my new hot tub, so your questions and waterbear's responses help. 🐵

I hope you do not have High TA (370 ppm) fresh fill water like I did. If you do, get some Muriatic Acid before starting your refill and balance task. I blew through most of my 1 lb canister of PH Decreaser (Sodium Bisulfate 93.2%) before switching to Muriatic acid to drop the PH down repeatedly after raising with aeration. I had no idea how soon I could retest the PH (how long it takes for the PH to settle at its low point after adding acid and whether that amount of time is different between powdered Sodium Bisulfate acid and liquid Muriatic Acid. I wanted to do as short of turn arounds as I could, to save time. Since I had no clue and could find no mention of it on this site or Google, I defaulted to waiting 30 mins after adding acid, until checking PH again, then starting the aeration, again for 30 mins. not knowing if 10 or 15 mins was plenty to raise the PH back up to 8.0.

Good luck in your process. It is a learning experience.

 

[Biggen]

5 hours ago, Davekro said:

Biggen,

I am having similar questions about how fast my Bromine level will drop from 24 ppm after  adding the Sodium Bromide Reserve after fresh fill on my new hot tub, so your questions and waterbear's responses help. 🐵

I hope you do not have High TA (370 ppm) fresh fill water like I did. If you do, get some Muriatic Acid before starting your refill and balance task. I blew through most of my 1 lb canister of PH Decreaser (Sodium Bisulfate 93.2%) before switching to Muriatic acid to drop the PH down repeatedly after raising with aeration. I had no idea how soon I could retest the PH (how long it takes for the PH to settle at its low point after adding acid and whether that amount of time is different between powdered Sodium Bisulfate acid and liquid Muriatic Acid. I wanted to do as short of turn arounds as I could, to save time. Since I had no clue and could find no mention of it on this site or Google, I defaulted to waiting 30 mins after adding acid, until checking PH again, then starting the aeration, again for 30 mins. not knowing if 10 or 15 mins was plenty to raise the PH back up to 8.0.

Good luck in your process. It is a learning experience.

 

Thanks for the response @Davekro.  Actually my water (City water) is soft so I have to add both Alk and CH to get them into the proper levels.  So no acid for me!

I plan on doing the drain and refill next week.  Waiting on some supplies (need Ahh some).  Hopefully everything goes well!