New Hot Tub Owner

[cschnurr]

I've had a pool for almost 15 years and have been a regular user of the forum.

My wife's been diagnosed with fibromyagia, and my arthritis in my ankle is starting to get worse. So last week we decided to take the plunge and installed a 1300 litre hot tub, with ozonator.

So far we're loving it!

I have been using the Bromine, 3-step method described on the form using tablets, bromide and MSP. The first week our daughter from out of town visited for a family wedding, and had three nights of hot tub festivities. We consumed an 1kg container of MSP in a week. The usage seemed high to me, but when I did the calculations of bather load-hrs, it was pretty much bang on. A 1kg container of MSP is about $16, so I 'm looking at the alternatives. (I understand the tablets have likely not dissolved yet).

I have read the sticky thread, "How do I use Bromine in my spa (or pool)?" several times and found it very useful. I would like some clarification on the use of Chlorine in a bromine pool.

1. Does the chlorine act in the same way it does in in chlorine pool, or does it also activate the bromide to produce bromine, or does it do both?

2. The sticky describes use of chlorine as shock. can I also use it for regular maintenance instead of MSP?

3. Does the use of chlorine with bromide, negate any of the advantages of using the bromine system vs a completely chlorine system.

Thanks

 

[MPurcell]

Liquid chlorine acts as an oxidizer just like MPS does. It converts sodium bromide into active bromine, and in the process produces salt and water. It is much more economical to use bleach/liquid chlorine, and also is relatively pH neutral, whereas MPS is acidic.

I feel that the sticky is a little misleading. I don't think of it as shock, but rather as an oxidizer. In the three step method, you should have the floater with the bromide tabs set to keep the tub at the same level of bromine ppm when there is no usage, and then use the correct amount of oxidizer to exactly offset the bather waste after each period of use. If the process is carried out correctly, there should never be any need to shock the tub.

It is not a problem to use liquid chlorine or bleach in a bromine system, and the chlorine does not stay in the form of chlorine very long, usually measured in minutes rather than hours. The problem that you read about is when bromine is added to a chlorine tub or pool, because the bromine will not go away, and if you add enough, you will have converted the tub or pool to bromine. The chemistry of chlorine use is not the same as the chemistry of bromine.

I use the bromine three step method with sodium bromide, tabs in the floater, and additions of 8.25% bleach after each soak.

Hope it helps.
Michael

 

[JVTrain]

MPurcell is spot on with the advice. You wouldn't necessarily have to have a bromine floater with an established bromide bank and an ozonator, as the ozonator will continuously convert some bromide to bromine for a base level of bromine, but not enough for recovery after multiple bathers. You'd still have to use bleach to bump the bromine level up after soaks. A floater might mitigate that need for the most part, but whenever I used bromine, I bypassed the floater and just used bleach after soaks and to bump bromine level up occasionally if the tub went with minimal use. I didn't like that bromine floaters tend to elevate bromide bank levels and add BDMH to the tub (a weak analog to CYA for chlorine). With recommended drain/refills every 90 days or less, the bromine floater wouldn't be much of a concern though.

My tub is currently a chlorine tub as I prefer the general aroma of chlorine over bromine, using the dichlor then bleach method.

 

[cschnurr]

Thanks for your advice.