Hello from a Cedar Hot Tub owner having trouble with sanitation

Cidiotskills

New member
Oct 19, 2021
1
Catskills New York
Hello everyone. Please forgive what may turn into a long explanation for what might be a simple question(s). Perhaps I should post this in anther topic and not in intros?

I have owned a wood fired cedar hot tub for a little over 3 years. It has no plumbing/filters. It’s from Snorkel and the stove sits inside the tub. It is surprising how little information is out there on how to properly sanitize for this type of hot tub and how much conflicting information there is. Even the company Snorkel doesn't seem to be 100% confident in their suggestions. There exists a lone, long complicated PDF, easily found, which I have read on wood hot tub care. It’s says chlorine is bad (attacks the wood), bromine is good. Snorkel says bromine is bad, chlorine is good. One simple site says just use industrial strength hydrogen peroxide, drain and refill frequently. Non chlorine shock comes up a lot.

There are some inherent challenges I face for sanitizing. We live in the Catskills and we Airbnb our house. We do not let guests use it. It does mean we are away from the tub for stretches. It gets used when we return. We use it for maybe two or three days and then sits for a bit. We have harsh winters and the tub can start to freeze. We can certainly drain and refill it as often as we want. We are in the watershed. We have more water than we know what to do with and it gets filled with very good spring water. The specs of the water are as follows. Very low alkalinity 14, low PH 6.4 and basically no hardness, no metals.

Now my problems may be user error. I'm sure they are. The sole instructions from Snorkel was to use a product called instant ions along with 1” trichlor chlorine tabs in a floater. Basically a mineral and low chlorine sanitize system. Also drain, clean (with a bleach solution) and refill frequently. I am not going to claim I was super on top of balancing the water. I found putting in a cup of baking soda brought my alkalinity and ph up to where they needed to be. I never worried about hardness. I probably should have been more on top of testing for the cooper level from the instant ions and add more instant ions as needed weekly. There are special test strips for this. It was easy to see if the chlorine tabs needed refreshing. I did drain, clean and refill frequently. After reading that long PDF I switched to bromine for a while using the Renew and Refresh products from Leisure Time. I struggled hard with that.

Over time the wood in the tub would start to get slippery and when it was drained it was if there was a slippery film over it. After asking around the general consensus was it was white mold. When the tub would dry out the wood would look frayed. I have now twice let the tub dry out and completely sanded it down and now I’m determined to never have to do that again. I’ve studied and researched and I now know how to balance my water including hardness. Thank you Trouble Free Pool and the Pool Math Calculator!

One of the things I thought may contribute to my problem is the water sits stagnant for long periods. I have recently built a DIY aeration system using pond aerators that I can run 24/7 in an attempt to keep the water moving. I’m hoping this will also help with freezing in the winter. The tub never totally freezes and of course unfreezes as soon as you fire it up.

Meantime during my month of sanding I found the Frog @ease system and I was intrigued. It seemed to present itself as a set it and forget it system once you balance the water. I did a lot of research and read some threads here and I do realize that their system is just clever packaging using readily available supplies and that “smart chlor” is not smart and is just 2000 Flushes with Bleach. Thanks to some threads here it’s clear the data sheets for both products are identical. Side note - people complain at the expense of the “smart chlor" cartridges. I broke one open and measured the amount inside. If you were to buy the same amount of 2000 flushes it would be the same.

I decided to invest in it. A mineral cartridge that lasts 4 months, and a constant supply of “smart chlor.” Along with my DIY aeration system it seemed like it could be the solution for not being with the tub everyday.

Now if you’ve made it this far here is my question. I’ve had quite the back and forth with a rep from Frog who’s been very helpful. I’ve told her the challenges and one thing she mentioned (of course after I bought a round of the @ease system) was that the “smart chlor” will only work when the hot tub is 94 degrees and above. She seemed to suggest that when the water cools down, which it will most of the time, the ‘smart chlor” will cease to sanitize effectively. It will mostly live around 30 degrees and below depending on the time of year. Well that’s a bummer if it’s true. Is it true?

It does seem that the Frog @ease system is just the same system that Snorkel was telling me to do, using instant ions and chlorine tabs. It's just dressed up in fancy packing and much more expensive. It was worth it to me if it meant I didn’t have to worry about being away so much.

If it’s true that “smart chlor” is ineffective a lower water temps would the same hold true for trichlor chlorine tabs? Are the minerals also not effective a lower water temps?

Maybe this is stupid question. If I drained the tub after using it some days and cleaned it and then filled it back up and balanced the water, during the period of non use with cold water would it need to be sanitized? Could I just check that the water is balanced, make adjustments and start sanitizing when I start to use it again. Drain and repeat?

I am open to learning anything that might be helpful in tailoring a solution so I never have to spend a month sanding my hot tub again.
 

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phonedave

Well-known member
May 30, 2012
1,016
Montville NJ
Pool Size
17000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Hayward Turbo Cell (T-CELL-5)
You have essentially two materials in your tub. Wood and powder coated aluminum (the stove)

When it comes to the concentrations in your tub, bleach should not hurt either the wood, or the stove. It may "fuzz up" the wood a bit, but that is cosmetic.

Now comes what I see as the biggest issue. Wood is porous, rough, and an organic material. It has many nooks and crannies that can harbor and protect all sorts of bacteria and other nasties. Even if somehow it was free of all of that, the very fact that it is an organic material means that it will react with the chlorine in your tub and use it up.

If this was a resin tub (or any other non-organic smooth surface) with a wood fired heater and no circulation I would say to balance your water, and when you are leaving for a while, run your FC up to SLAM levels and cover the tub, and SLAM it again when you go to use it again. However with the wood involved, I doubt it is going to hold FC for any amount of time.

I don't know how the tub is made, but if it has welds on it, I doubt they are sanitary welds, and so they can hold bacteria as well.

A floater with tablets may be your best bet. At least that way you have a steady supply of chlorine being added while you are away. Cold water slows down all reactions, including bacterial and algae growth, so cold water is just fine.

My understanding is that you are not supposed to drain wood tubs and let them out, or else they leak when you refill them until they swell back up.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
18,603
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Is the tub compatible with salt water? (Chlorine and acid both add chloride ions to water so if you are told to use chlorine for sanitation then salt should be fine). If you can use salt in the water (typically up to 3000ppm), then just get a drape-over SWG like the Saltron Mini.

Stay away from the @Ease system, it’s really more trouble than it’s worth.

You have a wood tub … it’s essentially a glorified bathtub. What do people do with bathtubs … they use them and then drain the water. Sadly, you’re never going to get long stretches out of the water in that tub, it’s simply not possible. So you basically need to fill it, balance it, sanitize as best you can, and then dump the water once it goes sideways. That might be a weekly chore but that’s really all you can do. In the interim periods, you’ll have to drain it and let it sit empty when you are not there.

One question - I know cedar is naturally a wood that doesn’t need to be treated since termites and other boring insects hate it, but can you seal the interior wood surface with a good quality waterproof wood sealer to help eliminate porosity and mold growth? That might be an option.
 

phonedave

Well-known member
May 30, 2012
1,016
Montville NJ
Pool Size
17000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Hayward Turbo Cell (T-CELL-5)
Is the tub compatible with salt water? (Chlorine and acid both add chloride ions to water so if you are told to use chlorine for sanitation then salt should be fine). If you can use salt in the water (typically up to 3000ppm), then just get a drape-over SWG like the Saltron Mini.

Stay away from the @Ease system, it’s really more trouble than it’s worth.

You have a wood tub … it’s essentially a glorified bathtub. What do people do with bathtubs … they use them and then drain the water. Sadly, you’re never going to get long stretches out of the water in that tub, it’s simply not possible. So you basically need to fill it, balance it, sanitize as best you can, and then dump the water once it goes sideways. That might be a weekly chore but that’s really all you can do. In the interim periods, you’ll have to drain it and let it sit empty when you are not there.

One question - I know cedar is naturally a wood that doesn’t need to be treated since termites and other boring insects hate it, but can you seal the interior wood surface with a good quality waterproof wood sealer to help eliminate porosity and mold growth? That might be an option.

I am no expert on wood hot tubs, but I did briefly look into them a while ago (they seemed interesting and quaint in a rustic sort of way).

From what I read, you have to let the wood get waterlogged. That is what causes it to swell, and make a tight waterproof seal between the staves. If you leave it empty so that the wood dries out, it will leak until the wood soaks up enough water again. I would assume that if you waterproofed the wood, you would have the same issue.

Again, I may be totally wrong, but that is what I read when I was looking into them.
 
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Newdude

Gold Supporter
TFP Guide
Jun 16, 2019
11,193
NY
+1 Dave. It’s the wine barrel principal for wooden hot tubs. It’s a thing. Now that you point it out, the sealer would solve one problem at the expense of another.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
18,603
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Buy a custom fabricated vinyl liner for it and … boom … problem solved. I think a nice, tacky vibrant blue with embedded glitter would look nice …
 

Ahhsomeguy

In The Industry
Jul 26, 2016
217
Vero Beach, Florida
Hello Cidiotskills: I believe there is a solution for you to get longer time duration between filling and dumping the water. Our testing of a new maintenance product called Aqua Clarity could be your ticket. The Aqua Clarity is an offshoot of the Ahh-Some Plumbing cleaner that aids in the removal of non-public health Biofilms and Slime-Forming Microorganisms. The Aqua Clarity will seek out all the tiny nooks and crevices in the wood shell and prolong the time you will get out of the water before you need to dump it. It will work synergistically with chlorine or bromine. We have had numerous covered test hot tubs, with filters and pump as is standard, actually go up to 13-15 days with very low to no sanitizer residual, no enzymes, no clarifiers or other chemicals used. We were testing the days we could go with little to zero intervention like when you go on a week or 2 vacation. The product did the job with ease. Just so you know, we do NOT want you to not treat any hot tub with an approved sanitizer. You need to always have adequate free available sanitizer levels for maintaining a healthy hot tub environment. These were "worst case scenario" tests. I have been using this method in my own hot tub here in Florida for over 2 years. I add a small splash weekly and maintain sanitizer. Water is always crystal clear, smells great, feels soft and refreshing and tests are performed on a regular basis with a reliable test kit, not strips. This little 6 ounce product is sold as a concentrate like the way some people still buy orange juice. Mix the small bottle with tap water in a gallon container with a child resistant cap. Add 1 ounce weekly for every 200 gallon capacity in your hot tub. In a 400 gallon hot tub this will last over a year. You need just this, a sanitizer and periodic pH and TA adjustments. This will work nicely in your snorkel wooden hot tub and allow you to enjoy crystal clear, fresh smelling and feeling water for a longer duration before you drain and refill. Please post your results should you decide to try it. The community would appreciate your comments.
 
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phonedave

Well-known member
May 30, 2012
1,016
Montville NJ
Pool Size
17000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Hayward Turbo Cell (T-CELL-5)
+1 Dave. It’s the wine barrel principal for wooden hot tubs. It’s a thing. Now that you point it out, the sealer would solve one problem at the expense of another.

I like a nice oaky hot tub water, low tannis, with top notes of chloramines.
 
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phonedave

Well-known member
May 30, 2012
1,016
Montville NJ
Pool Size
17000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Hayward Turbo Cell (T-CELL-5)
Buy a custom fabricated vinyl liner for it and … boom … problem solved. I think a nice, tacky vibrant blue with embedded glitter would look nice …

That's too classy. A blue tarp will take care of it just fine.
 

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phonedave

Well-known member
May 30, 2012
1,016
Montville NJ
Pool Size
17000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Hayward Turbo Cell (T-CELL-5)
Buy a custom fabricated vinyl liner for it and … boom … problem solved. I think a nice, tacky vibrant blue with embedded glitter would look nice …


I just happened to be looking at saunas and I found this

 
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