Chlorine only??

[Tokaydad]

We are new hot tub owners with a used older model Hydropool. We really enjoy it and along with our 2 teenage sons, use it daily. I have the chemical balance perfect, using bromate and chlorine. I use a floater that dispenses the bromate tablets and add liquid chlorine as needed.
We are very happy BUT the smell of the bromate bothers both my wife and I. Once I am in the tub, I have a runny nose and sneeze all the time I am in it.
Can we use chlorine only and if so, what changes will I need to make in my chemical use?

[chem geek]

It's not bromate, but bromine, that you are using.  Bromine in the tabs, and sodium bromide for what you can add to the water initially (not sure if you did that part).

Yes, bromine smells different than chlorine and some people don't like it.

Yes, you can use just chlorine, but once you've used bromine, the only way you can have a chlorine tub is to change the water.  Before you change the water, I suggest you use Ahh-Some to get rid of any built-up or leftover greases, oils, or biofilms in the spa.

Just note that if you use chlorine in your spa, you will have to add it every day or two if you have an ozonator and at least twice a week if you don't have an ozonator.  If you soak every day or two (it sounds like you do) then this should not be a problem, but if you are only using the spas on the weekends then chlorine will be more maintenance for you.  You can use either the Dichlor-only method or you can use the Dichlor-then-bleach method where the latter will let you go around twice as long between water changes.  With the Dichlor-then-bleach method, you start out using Dichlor until you've cumulatively added around 33-44 ppm FC which will have built up around 30-40 ppm Cyanuric Acid (CYA).  After that you use regular unscented (NOT splashless, outdoor, scented, etc.) bleach such as Clorox concentrated 8.25% bleach.

If you use the Dichlor-then-bleach method, then before you switch to using bleach you need to lower the Total Alkalinity (TA) in your spa (see Lowering Total Alkalinity to around 50 ppm and need to add 50 ppm Borates (most easily added from boric acid you can get from Duda Diesel or from The Chemistry Store (though you could use ProTeam Gentle Spa, it's not as pH neutral as boric acid -- it has mostly boric acid but also has sodium tetraborate that raises the pH too much),

[d00nut]

Or you could just use a nature 2 with some dichlor and MPS.  Drain the spa, install the nature 2 and shock with dichlor.

Easy peasy

[chem geek]

Instructions for the Nature2 with MPS (and occasional Dichlor, usually weekly) approach is described in the Nature2 Spa Mineral Sanitizer Owner's Manual.  This is a low chlorine system -- pretty much no chlorine most of the time except when you shock with Dichlor.  It's more expensive than Dichlor-only which is more expensive than Dichlor-then-bleach.

[Tokaydad]

I installed the Nature 2 about 10 days ago. I drained the tub, it was due anyways. I filled it and drained it again. I also cleaned the filter. Installed the Nature 2 and am using chlorine tablets in my floater. Great water, clear and clean with no odor. All balanced as well. I'll update as time goes on.
My oldest son (21) is having a party on Saturday night so that might be the big test !

[chem geek]

Remember that with any of these systems you need to add enough oxidizer after a soak to oxidize the bather waste.  So a higher bather load needs more oxidizer to be added.  With Nature² that means using more MPS.  If you have an ozonator then that will help, but it will still need MPS to be added (though perhaps half as much as with no ozonator).

[hottubdan]

Chlorine tabs are meant for pools. Very acidic.  Since you are using Nature2 you should get the tabs out.  Just use MPS shock with each use and chlorine once a week.  Follow instructions that came with your Nature2.

[d00nut]

Agree with hottubdan.  Say no to chlorine tabs.  Will do more harm then good.

[Tokaydad]

Now a month in using the Nature 2 and a floater with the chlorine tabs that I bought to be used in hot tubs. Water has stayed balanced with no chlorine odor and the water is crystal clear!!

[Dr. Spa™ Ret.]

Chlorine tablets are "trichlor", and shouldn't be used in a hot tub. They're intended for pools and water under 80 degrees. They're extremely acidic and at hot tub temperatures dissolve at an incredibly high rate. Will they work for a short time (without causing damage)? Sure, but so will heating your home with a BBQ in the living room.

[chem geek]

It's not that the Trichlor tabs are instantly a problem but if the floater parks itself near a spa edge while the pump is off the acidity from them can damage the spa surface (the same thing happened to me a decade ago in my pool where the Trichlor pucks in a floating feeder rusted stainless steel mounts).  With Trichlor, every 10 ppm FC will lower the TA by 7.1 ppm so if you don't balance that then the pH can end up crashing and causing damage.  Trichlor usually dissolves too fast in hotter water so the feeder would need to be designed to have lower than normal water flow through it.  That same 10 ppm FC would lower the pH from 7.5 to 7.1 (with 100 ppm TA) if there were no carbon dioxide outgassing.

[sksmoker]

As a new hot tub owner I am going to say I know nothing compared to the knowledgeable people here. What I will say is this comes down (I think) to a regional difference. Being in Canada myself in the west, all you see is mini trichlor tabs in dispensers here. Dichlor is not common at all up here for whatever reason. When we were looking for a hot tub we went to every store in my city and even outside our province to look at different brands. All the dealers I asked for chlorine in the tub had the same answer. Mini chlorine tabs in a dispenser, some type of water "treatment" (cleaning cube, cleaning liquid, it varied by store which brand each carried) and shock with a "pouch" of product (which turns out to by in my case 50% dichlor and 50% mps in a 40 gram bag) of "shock" per week.

I know this is making your skin crawl for the majority of readers here in the US but in 2 western provinces here, trichlor tabs in hot tubs is common. I aksed about dichlor each time we went looking and mostly got blank stares and some just said "you use that for shock".

Now I know your going to say that it will void your warranty, and I followed through on that. The manufacturer stated as long as the mini pucks are in a dispenser and the large pool pucks are not used, warranty is not affected. I know it goes against everything you read here but I think there has to be some give and take. I test my water daily and keep an eye on the water to keep it as perfect as possible

So far my readings in my tub are:

FC: 2.5
CC: .5 (city water has chlorine right from the tap)
PH 7.6
TA: 80
CH:170
CYA: 38

I have a taylor k2006 test kit and have read my brains out in this forum and another regarding water chemistry and keeping things in check. I think I have also worn out the poolcalc/pool math website as well with all of my water testing

Just so you know, my dispenser is open at the "2" mark on the floater, which is about 1/8" of an inch to keep my FC numbers in range without letting it drop to 0 or spike it. I go through a stack of 5 "mini pucks" every 10 days and keep the hot tub at 101 at the moment. If we have people over, I just open up the dispenser a bit after and make sure I test to keep at eye on the FC level. I use Baking soda  weekly to keep the ta/ph in check and also add Borax to bump up the PH to 7.6 so I don't take the TA too high with the baking soda alogn with weekly shock with my 50/50 puch and a "cleaning cube"

According to the pool calc, With my numbers, I am at "0" with trichlor, so it can't all be doom and gloom.

I guess you just have to use your head if using this stuff as others have said here.

[Tokaydad]

Thanks sksmoker. I was very frustrated with people telling me I was doing things wrong and was looking at other forums as well because of it. I was confused also because a lot of on-line suppliers offer the mini pucks/tablets of chlorine.
I am in Ancaster, Ontario and visited 4 different hot tub stores and all suggested the method I am using after I explained the problem I was having with bromine. I am using a floater/dispenser the same as yours with my set at about 1 3/4. The mini pucks/tablets are made specifically for hot tub use and not pool pucks. I have no chlorine odor and my water is crystal clear and all my tests within spec.
I'll continue with the method I'm using as it works for me.