Smell from water on recent first/fresh fill

[scubaspock]

Sorry to start a new thread but I didn't want to derail anyone else's with questions about my situation. I'll post the situation point form to hopefully make it easy to follow:

• Background: I'm a summertime-only successful pool owner/operator (2400gal above ground), never had issues balancing water over multiple years (granted, only ~6mths each deployment). Also I'm an engineer so in theory I won't have trouble with simple math/calculations.
• I just took delivery of a used spa (400 gal, model year 2006), wired it up and filled it with fresh water Oct 19.
• Immediately after filling I added a touch of liquid chlorine and a healthy dose of Ahhsome, ran the jets for a while and made a ton of bubbles. A "normal" amount of gunk came out (versus pictures I see from others). If it was truly disgusting I was prepared to do it again, but it didn't seem necessary.
• Drained the water/Ahhsome and cleaned the whole tub interior (using water/wipes) to remove all the gunk that Ahhsome left behind as it drained.
• Rinsed the spa (walls, footwell, etc.) while still draining to complete the flush/purge. Now we "should" have established a clean spa & plumbing baseline to build from.

Next:

• Filled water again
• Added baking soda to increase TA just over 100
• pH was a touch high so I added some sodium bisulfate granules to reduce it into the ideal range
• Added 30g of bromine granules and tested -- strip went bright colour like in "shock" range
• Waited for bromine level to drop to ~5ppm before using it, and we've used the spa only a couple times (two adults)
• Each time we use it I add a bit more bromine granules and make sure the strip shows at least light colour

But now when I open the cover (also preowned) there's a poor smell. It's not really noticeable if the cover is off and you're just bathing in the water but when the lid is first lifted it is pretty strong (but then, I'm sensitive). It doesn't smell like "chlorine" it's something "else" (sorry, I can't think of what it smells similar to!). I have tried:

• Adding more bromine granules (10-20g at a time)
• Adding non-chlorine shock (oxidizer)
• Keep lowering the pH as I understand the bubbles will cause it to increase
• Testing, testing, testing -- everything looks "ok" to me, but I haven't taken a sample to the pool store yet
• What I DON'T have: a bromine tablet floater (Amazon delivery delay! It is arriving tomorrow or Wednesday.), and being in Canada I don't have a Taylor test kit (yet)

However, despite reading the sticky thread (over and over), I'm not as familiar with bromine as I was with chlorine. Are my tests (strips or OTO drops) measuring the "bromine bank" or the "activated bromine" (as I understand it, hydrobromous acid)? When I add bromine granules do I need to also add oxidizer to activate the bromine?

My theories:

• I simply don't have enough bromine in the water yet. I have noticed it read zero on a test once. I added some right away but it did briefly drop to nothing.
• The old cover has something gross in it, not visible but in or beneath the vinyl.
• I'm not "activating" the bromine somehow.
• Without the tablet floater, the bromine level is too much of a whipsaw and isn't stable for long enough to sanitize properly.
• Hot tub steam just smells gross when you first open the cover? Am I being too sensitive?

 

[Mdragger88]

I have a feeling it’s partly the bromine. Bromine can smell weird & be irritating. Maybe also some of the smell is the old cover. Unzip the cover & remove the foam cores. They should be completely sealed, if they aren’t & are deteriorated/water logged order some new ones. You’ll likely never get the funk out of the foam. You can try drying/airing them out & re sealing them with visqueen temporarily.
The cover itself can be cleaned inside & out & reused if it’s not torn up. I’ll try to post some links for known suppliers in a bit.
@JoyfulNoise can probably elaborate on the chemistry that causes some of the smells/irritation with a bromine system.
Is there a particular reason you went with bromine? Most here use chlorine (dichlor then bleach method) with their tubs so there’s alot more support for that method.

How do I use Chlorine in my Spa or Hot Tub?

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.troublefreepool.com

 

[Mdragger88]

Here’s one several folks here have had good experiences with - they sell replacement foam & complete covers

Hot Tub Covers & Replacement Spa Covers | BeyondNice

Find high-quality hot tub covers by brand or shape at BeyondNice! Our American-made spa covers are factory direct, ship free and include a 5-year warranty.

www.beyondnice.com

Also some others in this thread

Spa cover recommendations

I’m looking into a replacement cover for a Coleman 705 series hot tub. Any recommendations for what company to go with? Thanks in advance, David

www.troublefreepool.com

 

[scubaspock]

Just tested the water again using a Hach AquaCheck 7 test strip (that has never steered me wrong with a chlorine pool). Reads as ~10ppm "total bromine" (same colour swatch as 5ppm total chlorine) and pH is in check.

Thanks for the suggestions; I'll try cleaning the cover (it's only temporary as I'm ordering a new custom-fit one but those take ~weeks to get). Hope that resolves it because we're in the rainy season in Vancouver now!

I went bromine for a couple reasons:

• A desire to avoid CYA buildup and draining/refill because of overstabilization, which is avoidable with liquid bleach but for some reason my spa mfr (Hot Springs) says NOT to use liquid sanitizer so who knows
• Google results (including this forum some places) suggest bromine has no smell (but of course bromamines and sanitization byproducts will smell)
• I thought bromine was a better sanitizer at 100F than chlorine is -- perhaps that's irrelevant?
• Maybe I just wanted to experiment and learn something new? was chlorine too easy? Actually, the fact that bromine was more expensive may have contributed to the "premium" sensation of that choice.

I presume I can switch back to chlorine at the next purge/refill if I want to. I'm definitely noticing that bromine stays on/in the skin for longer than chlorine does. A shower washes it away, but I do a spa soak in the evening and don't really want to shower until the next morning.

 

[JoyfulNoise]

Combined bromine (bromamines) show up as total bromine (free bromine + combined bromine), there’s no real way to differentiate what you have. Bromamines can be as smelly or worse than chloramines. You could also have some residual Ahhsome in the plumbing that is being oxidized by the bromine and creating smelly compounds. They will build up in the airspace between the water level and the cover. As @Mdragger88 said, your cover could have mold inside it as well being that it was a used tub.

I suggest checking out the cover first and then looking for chemistry issues. You may need to purge this fill sooner than intended and do another, smaller round of Ahhsome. If you do go that route, you need to get as much of the Ahhsome water out of the pipes as possible. Air compressors and shopvacs are good for that.

 

[scubaspock]

That's a good theory to add to the list: residual Ahhsome from the plumbing. I thought I was doing well by continuing to drain while filling/rinsing but there are a number of pipes (for the jets etc.) not included in that process that probably held some water/Ahhsome mixture. Do you think the bromine will eventually oxidize all that Crud or there's no choice but to purge it sooner?

 

[JoyfulNoise]

That's a good theory to add to the list: residual Ahhsome from the plumbing. I thought I was doing well by continuing to drain while filling/rinsing but there are a number of pipes (for the jets etc.) not included in that process that probably held some water/Ahhsome mixture. Do you think the bromine will eventually oxidize all that Crud or there's no choice but to purge it sooner?

Your nose knows ... maybe it will get better if you do shock level of bromine (roughly 16-20ppm Br on the test) ...

 

[scubaspock]

Thanks, I'll just monitor it. It's not "bad" just not as neutral as I thought it would be. I'm definitely taking a deep breath in and THEN opening the cover, a good few minutes before bathing. That initial hit from the trapped airspace is worth venting

And hey, with enough bromine my nose won't even work any more so problem solved!

 

[JoyfulNoise]

Do you ever open up the tub during the day ? A little bit of sunlight (UV) can go a long way .... letting recreational water bodies "breathe" is a good thing ....

 

[scubaspock]

Not much UV even in the daytime up here for the rest of the fall/winter season but I can definitely vent it out. Thanks for your suggestions!

 

[Mdragger88]

The test strips will steer you wrong, you definitely need an accurate test kit.

Pool Test Kits - Further Reading

www.troublefreepool.com

* there are many people with hot springs tubs here who use liquid chlorine with no issues - fwiw the mfgr of my tub says to pour dichlor & acid into the filter compartment, I don’t follow this advice either.
Using Liquid chlorine in appropriate doses will not harm your tub unless you spill it on the shell/surfaces & don’t rinse it off.
I have a drape over swg (saltron mini) that handles most of my chlorination so my liquid chlorine additions are quite small although they are generally only a few ounces otherwise.
* a properly maintained chlorinated tub should also have no smell
* either sanitizer (bromine/chlorine), if maintained at the proper levels, should be equally as effective sanitation wise.
* bromine is more expensive but that doesn’t necessarily make it better
People who aren’t irritated by bromine tend towards it because it is a little more hands off than the daily/every other day dosing of chlorine. I personally find bromine harsh, complicated, & also a little mysterious. I like testing & knowing exactly where I stand then using PoolMath to record & calculate all adjustments. Bromine/bromide products/values aren’t listed in there.
Many, like myself, use a drape over salt water chlorine generator to lessen the burden of daily dosing with a chlorine tub. Its the best of both worlds in my opinion & definitely less complicated testing & chemical wise since I already operate a chlorine pool.
You definitely can switch to chlorine after your next drain/refill. Some people alternate for various reasons.
You can turn a chlorine tub into a bromine tub but to change from bromine to chlorine you must completely replace the water.

 

[Methuselah]

I just purged for the first time using Ahh-some! and was concerned about getting out as much of it as I could. During draining I directed hose spay into each of the jets as the became uncovered. I suppose it would not have done much if I wasn't also running a sump pump and open bottom plumbing drain...

I can't speak to reasoning why a manufacturer "demands" chlorine avoidance, but on a used tub with no warranty I'd have ignored that advice unless you just have to have a floater dispesing system.

Gotta agree with the help you got though, sounds like interaction from purge, cover (foam?), or what you said about levels vs. killing off and venting bad stuff.

 

[Ahhsomeguy]

Hello Scubaspock: There is absolutely no need to worry or spend much extra time trying to get every drop and ounce of purged water out of your plumbing and jet lines after a purge with Ahh-Some. Ahh-Some is not what you are smelling. Ahh-Some has a delightful almond aroma that is very faint to the most sensitive nose. I hear of people who spend so much time trying to remove all the water from the lines after a purge. This is not necessary. So you have a gallon or two left over after you drain the tub. You may see a few remnant floaters upon refilling and starting the jets. Your filter will get these in short order or you can simply wipe them from where they collect. Sure, drain as much water as you can after a purge. Don't knock yourself out trying to get every ounce out. It is a waste of time and effort.

 

[scubaspock]

Thanks everyone! I just might switch to chlorine (maybe even SWG??) at the next fill. I'm getting a new cover in a few weeks so I'll see if that resolves it. And I know I need a proper test kit they are just very expensive and hard to get in Canada. I'm waiting for my next trip to the USA to bring one back with me. The test strip only tells me if I have "none," "some," or "lots" of sanitizer but that's about it. I have a basic OTO/pH test kit with the clear cylinder to compare the colour and I don't like it very much. Will definitely get FAS-DPD when I'm able to.

 

[Mdragger88]

Thanks everyone! I just might switch to chlorine (maybe even SWG??) at the next fill. I'm getting a new cover in a few weeks so I'll see if that resolves it. And I know I need a proper test kit they are just very expensive and hard to get in Canada. I'm waiting for my next trip to the USA to bring one back with me. The test strip only tells me if I have "none," "some," or "lots" of sanitizer but that's about it. I have a basic OTO/pH test kit with the clear cylinder to compare the colour and I don't like it very much. Will definitely get FAS-DPD when I'm able to.

Some in Canada have had luck recently with ordering on amazon

 

[Newdude]

Or this way

Help with Tf-100 / tftestkits.net for Canadians

Hi all Just joined this forum - blown away by the quality of content. In the process of building my first pool and went on tftestkits.net to get a TF-100. I am in Canada and since tftestkits.net do not ship over the border, I purchased a mailbox redirection service at the border to import the...

www.troublefreepool.com

 

[scubaspock]

Just to close the loop here, I finally got the brand new cover I ordered. Weird smell is gone instantly. Even though the older one looked fine, there was probably something funky hiding underneath the vinyl. Glad to be moving on with nothing but happy dipping!

Side note, and definitely a discussion for another thread, but I'm planning to take some of the advice above and try a drape-over SWG and switch to chlorine. Maybe after I run low on bromine tabs/granules