How to keep ice bath water clean

In this article, I will show you the exact step-by-step process it takes to build the exact same chest freezer ice bath setup that I use.
There are many different ways to build an ice bath, and it’s very time consuming to figure out which components exactly you should use. That’s why in the following guide, I will show you exactly which items you need, how to set them up, and how you to operate them. 
By the end of this article, you’ll know how to build the same ice bath setup with digital temperature control, filtration system and sanitation solution at the lowest cost, with the lowest time investment possible.

This I’ve been using this exact setup as a cold tub for several months now, and it’s working flawlessly.  It’s amazing for doing cold therapy, for athlete recovery or for practicing the Wim Hof Method.
And it’s so great that you can set the water temperature to the exact temperature that you like.
You can even gradually reduce the temperature every day by 0.1°, or 0.5°, or however much you like. 

In this article, you’ll learn how to take care of everything so that you’ll be able to operate everything and know how to keep the water quality in check. 
Some of the features that this setup offers:

• Digital water temperature control (with 0.1° C/F increments)
• Water temperature range between room temperature and 0° C / 32° F
• Filtration and sanitation system
• GFCI protection to prevent electric shocks
• Lid without selfclosing mechanism (so that you can't get locked inside)

How to Use this Article

This article is divided into the following three steps, which will get you to your own DIY chest freezer ice bath setup as quickly as possible:

• Step 1: Buying the Components
• Step 2: Building the Ice Bath
• Step 3: Using and Maintaining the Ice Bath

Before we get into it, a quick disclaimer:
Implement this article at your own risk. You will void the warranty of the chest freezer (and possibly of other components), and whenever there is water and/or electricity is involved, then there’s also an inherent health risk present.
I will do my very best to inform you of all the hazards that I’m aware of and present strategies to handle them, but ultimately you’ll still have to proceed at your own risk.
That being said, let’s get into it!

Step 1: Buying the Components

Below you can find the complete list of items that you need to build this setup. Later in the article, I’ll provide more information on some of these items, and I’ll link again to the items there as well.

Before you buy anything, I recommend you read through the entire article. The additional information in the later sections will make it easier for you to judge which of the components you want to buy. 
If the exact component that I used is not available, then I picked the best alternative, which will work just as well and linked that instead.

(Note: The lists below contains affiliate links, which means I get a small commission if you decide to purchase something through these links. This comes at no additional cost to you and I’m giving you my sincere promise that I’ll only recommend products that I truly believe in, and would also recommend to my family and friends.)

Key Components

These are the key items that you’ll need to get started.

• Chest Freezer (view on Amazon)
• Sealing Material: JB Water Weld (view on Amazon)
• Digital Temperature Controller (view on Amazon)
• Filtration Pump (view on Amazon)
• Ozone Generator (view on Cold Plunge Shop)
• GFCI Safety Adapter (view on Amazon)

Additional Components & Accessoires

Some of these items you may already have at home or prefer to buy at a local hardware store. 

• <g data-name="Layer 2" id="Layer_2"><path d="M20,4V2H18V4H16V7a3,3,0,0,0,2,2.82V16H14V2H2V22H14V18h6V9.82A3,3,0,0,0,22,7V4ZM7,19H5V17H7Zm0-4H5V13H7Zm0-4H5V9H7ZM7,7H5V5H7Zm4,12H9V17h2Zm0-4H9V13h2Zm0-4H9V9h2Zm0-4H9V5h2Z" /></g> Power strip with surge protection and at least 3 sockets (view on Amazon)
• Long Garden Hose to Fill and Empty the Ice Bath (view on Amazon)
• If needed: Adapter to Connect Hose to Indoor Sink Faucets (check size & view on Amazon)
• Zip ties (view on Amazon)
• Box to Contain the Electronics (buy at your local hardware store)
• Plastic Box with Flat Sides to Scoop the Last Bit of Water Out (view on Amazon)
• Plates to place in front of the freezer (buy at your local hardware store)

Additional Reading Material

There are many different ways to build such an ice bath setup. If you’re interested in learning about all the other options, then I highly recommend you have a look at the book “The Ultimate Chest Freezer Cold Plunge DIY Guide” by John Richter.
It’s a very comprehensive guide with 266 pages, covering pretty much every option you can think of.

It’s available both as an eBook and as a paperback, and the author, John Richter, was so kind to exclusively offer readers of ScienceBackedHealth.com 15% off.
Just use the coupon code “SBH15” during the checkout process. Thanks, John!

John also runs an awesome Facebook group, where you can join to connect with other ice bath builders and ask questions.

• eBook: The Ultimate Chest Freezer Cold Plunge DIY Guide (15% off with code "SBH15")
• Paperback: The Ultimate Chest Freezer Cold Plunge DIY Guide (view on Amazon)
• Facebook Group "Chest Freezer Cold Plunge"

A Word on Choosing a Chest Freezer

Maybe you can find a used chest freezer locally, or you don’t want to go with the one recommended in the list above for other reasons. In that case, a quick word on some things to look out for when choosing a chest freezer.

Picking the right freezer size for your cold tub setup is very important.
The one recommended in the shopping list above is large enough so that the water goes up to my neck, with the shoulders comfortably covered in water (I’m 183cm / 6 feet).
So this size will work for most people, except maybe much taller people.

If you’re unsure about the size, then just look up the inner dimensions of the chest freezer, and use tape to mark the size on a wall and on the floor in your home.
Sit right next to the wall, and you’ll get a very good feeling about the size.

You’ll also want a chest freezer that has a lid without a self-locking mechanism, and with a lid that stays open in a stable way when you open the lid.
This should apply to all new freezers, but it’s important to look out for if you decide to go with a used one.

Step 2: Building Your Ice Bath

Once you have all the components, then it’s time to set everything up!
First, we’ll go through everything you need to know on the individual components and then, as a last step, we’ll connect it all together.

Safety First

Since we are filling a chest freezer with water, this means we are adapting a device to hold water that isn’t meant for holding water, and that is also connected to electricity.
That’s why we need to strictly adhere to the following two safety guidelines to prevent electric shocks.

1. Using a GFCI safety adapter (ground fault circuit interrupt)

• GFCI Safety Adapter (view on Amazon)

In the case of an electric short circuit, this adapter is supposed to shut off before any harm is done.
If you’re not absolutely sure that the power outlet to which the freezer is connected has GFCI, then buy an external GFCI safety adapter, like the one recommended above.
This GFCI gets plugged directly into the electric socket, and ALL the other devices are connected only to this GFCI (by using a power strip).
See more details on this on the wiring diagram that follows below.

2. Never touch the freezer while connected to electricity
Find a way how you can ensure that you’ll always follow this.
An example could be: Running the extension cord over the freezer itself, so that before you open the lid, you need to unplug it

Let me send you a link to this article by email!

Ice baths can have a positive impact on several aspects of your health.
However, there are many more factors that are critical to reduce chronic disease risk and optimise your health.

Learn how to apply the knowledge of the world’s leading experts on health and longevity to your own life
Schedule a free coaching session by clicking the link below.

• Sealing Material: JB Water Weld (view on Amazon)

Almost the entire process of building this ice bath is very simple and basically plug-and-play, with one exception that requires a bit of time:
The sealing or lining of the freezer (more on the difference between these two options follows below).

Before you fill the freezer up with water, you should seal all the seams, so that water cannot leak inside and damage the freezer.

Placing the sealing material over the seams requires a bit of time invested, but once you did that, the rest should be super easy.

In DIY chest freezer ice bath building often aquarium-silicone has been used as sealing material.
But reports online show that in some cases, this can cause problems in the long term.
The much better way is to use epoxy putty, as linked in the components list, to seal the chest freezer.

The most commonly used product for that is called “JB Water Weld.” It’s even safe to contain drinking water, and it’s available in different sizes and bundles.
A chest freezer of the size linked in the shopping list above will require around 25 to 30 tubes of the 2 oz. version of JB Water Weld.

Before you go ahead and seal the seams, you need to remove EVERYTHING inside the freezer:
Trays, compartment, or dividers, as well as any rails and remainders of glue that is used to hold the compartments or dividers in place.
So that you end up with nothing but bare walls inside your chest freezer, otherwise you’ll not be able to seal the seams fully.

There’s also a plug hole and plug on the inside of the freezer, which you shouldn’t remove. However, you will have to seal around that as well. 

How can you then drain the water, without using the plughole? We’ll go through the process in step 3 of this article.

There is an upper seam going around the freezer that I recommend sealing as well, in case you hop in the ice bath a bit too quickly, and the water splashes around.

Alternative to Sealing: Lining

An alternative to sealing the seams would be lining the entire interior of the freezer with some form of an inner liner.
Pond liners, for example, have often shown to deteriorate quickly, especially if you decide to go with ozone as part of your sanitation solution (more on that later).

One thing that people seem to use successfully is “Line-X.” This is a professional material that you can’t apply yourself. You need to bring it into a shop.

If that’s something that’s feasible for you (if let’s say, you have access to a pickup truck or van), then you can google “line-X” around you to see if there are shops offering this.

Then just call them up and ask for a quote.
You’ll want to go with their highest-tier material, which is VOC-free (volatile organic components), so as to not introduce any health-damaging compounds into the water.

Also, ask them if you need to seal the seams with epoxy upfront or if their liner will take care of that already (you might have to bring the freezer in or send pictures for them to evaluate that).

Water Temperature Control

• Digital Temperature Controller (view on Amazon)

Many ice bath owners just control the temperature of their chest freezer on a time switch, which makes it run for a selected amount of time every day. 

I think there’s a much nicer and more consistent way to solve this, which is fairly inexpensive and very easy to setup:
A digital temperature controller, which has a small temperature sensor that goes into the water.
The temperature controller then ensures that the chest freezer is only running if the water temperature is above the desired water temperature, which you have set.

Later in the article, you’ll find a wiring diagram that shows exactly how to connect everything together. There you can see that the controller itself is placed in the box next to the chest freezer, and it’s connected to the power strip. 

The power cord of the chest freezer then is connected to the power socket from the temperature controller which is labeled “cooling” (and not to the one labelled “heating,” since we’re running an ice bath and not a hot tub. Makes sense, right?). 

With the temperature controller that I have recommended in the link above, there are basically only two things that you need to set up:

• Setting the “target setting” as the water temperature that you’d like to have.
  You can achieve this by holding down the “set button” for three seconds, then using the arrows to select your temperature, and then pressing the “set button” again for 3 seconds
• You’ll also want to set the temperature range, meaning:
  How many degrees the water can warm up above the set temperature before the freezer should kick in again and cool the water down again to the target temperature.
  Mine is set to a range of 0.5°, which makes it kick in a couple of times a day.
  If you set it to a bigger temperature range, let’s say 2.0°, then the freezer will turn on less often, which might extend the lifespan of the freezer.

Note: The temperature controller that I recommended in the components list has a built-in compressor-protection. This means the freezer won’t get turned on and off more than once every couple minutes, to extend the lifespan of the freezer’s compressor.
So there is no “flickering” that turns the freezer on and off multiple times if the temperature is just on the verge of your set temperature.

• Filtration Pump (view on Amazon)

Let’s talk about water quality for a minute. There are two components that your ice bath setup should have: Filtration and sanitation.

A filtration pump serves different purposes:

• It gets the water moving, which is good for the water quality
• It filters out small particles, such as from skin or hair

Water filtration will have a big impact on the water quality of your ice bath. Every couple weeks (depending on usage of the ice bath) you can simply take the cartridge out, and clean it with a water hose.

These pumps are meant to run 24 hours a day for optimal effects, and this is what I recommend as well.
The pump is always running, except while you are using the bath (since you should always unplug the freezer in advance, remember?).

Thanks to the water outflow of the pump, you’ll also visually see if the ice bath is connected to electricity, which will help to remind you not to use it while the ice bath is plugged in (see the section on safety for more on this).

To increase circulation, you can cut off a short piece of your hose, and attach it to the outflow of the pump. So that the pump sucks in the water near one end of the ice bath, and sends the filtered water out near the other end of the ice bath (this is optional).

Note: The recommended model linked above does not have a UV-C lamp for sanitation purposes (which many pond filtration pumps have). Having a UV-C lamp is not needed for sanitation of our ice bath, since we’ll be using an ozone generator (see next paragraph below) which has a far greater sanitation effect than any UV-C lamp in a filtration pump. The filtration pump linked above has a far stronger filtration effect than those of pond filtration pumps, which is why I recommend it, in combination with a powerful ozone generator for sanitation.

Water Sanitation

Filtration on its own, or the fact that the water is really cold, isn’t sufficient already.
We also need some form of sanitation. 

It’s a common belief that very cold water will stay clean on its own, but that’s not true; unfortunately, It will go bad rather quickly without sanitation.
There are many different options when it comes to sanitizing:

Not Using Any Form of Sanitation

If you don’t use any sanitation and are using the bath once every day, then it will only take a couple of days until the walls get slimy and algae start to build up.
So the water would have to be exchanged at least once a week, which is not very ecological and is pretty time intensive. Which is why I don’t recommend this approach.

• Ozone Generator (view on Cold Plunge Shop)

This is the sanitation method that I use and that I’m recommending.
Ozone generators pump ozone (which is a gas) into the water. Ozone has strong sanitizing effects.
This is one of the more natural sanitation methods, and it has the advantage that no chemicals are necessary.

For me, I like to use the ice bath first thing in the morning, and then just towel off and get about my day. 
For this, ozone generators are ideal, because there are no chemicals in the water that you’d want to shower off.

The model I’m recommending in the link above has a much higher ozone output than the cheap entry-level models that can be found online. It is suitable for sanitizing containers with up to 2’000 gallons or 9’000 liters volume, which is more than enough for every ice bath. 

Using a powerful ozone generator such as the one linked above will greatly increase the duration that the water stays clean and reduce how often you need to exchange the water and scrub the inner walls of the ice bath, which is why I believe it’s a worthwhile investment.
In combination with the recommended filtration pump the water only needs to be exchanged every couple months (if proper hygiene is followed, see the chapter below on using the ice bath).

Cheap models (in the $40 to $80 range) are built to sanitize small containers such as kitchen appliances. Their claimed ozone ouput (miligrams per hour) is usually vastly exaggerated, which explains their limited sanitation effect. 

The ozone generator that I recommend can also be run on a timer switch for several hours a day, while entry-level models often have a limit of 30 minutes and can’t be run on a timer (since a button needs to be pressed every time).

By using the timer switch (such as this one from Amazon) you can run the ozone generator anywhere from 1 – 4 hours per day for optimal sanitation, depending on the usage of the ice bath.

A note on material compatibility with ozone:
Freezers that have bare aluminum inner walls can react to the ozone gas and show discoloration over time.
If you want to avoid this, then you could choose a freezer with white inner walls, or that is lined with materials like vinyl, pond liners, polyurethane, JB Water Weld, and so on.
Chest freezers with bare aluminum inner walls can easily be pained or coated. Many manufacturers of paints and liners know if their product is compatible with ozone.
You could also simply place a pond liner on the inner walls of the freezer.

Chlorine and Bromine

Chlorine and bromine are two popular ways to disinfect pool water.
If your daily routine allows for a quick shower after the ice bath, then using chlorine or bromine would be the easiest option, since this will keep your water clear for months.

If you go with this route, then you can buy chlorine or bromine at every DIY store or pool store if you have a local one.
Just use the suggested quantity of chlorine or bromine for the amount of water that your freezer holds. These chemicals, for example, often come with dispensers that just float on the surface of the water.

Distributing the Load on the Freezer

There are two more things that I would recommend doing.

1. Removing any wheels, feet or rails from the freezer
Most freezers have wheels, feet, or rails, as does the one linked in the shopping list.
They are under a lot more weight than intended since the freezer is filled with water.
So the safest way would be to remove them, if possible, so that the weight gets distributed more evenly.

2. Using Support Plates under the Freezer
The floor of the freezer’s inner compartment kind of “hangs” in the air.
This is why your feet can leave dents on the inside of the freezer’s floor.
To minimize this, it’s recommended to put some supporting materials underneath the freezer, for example, some rubber mats of the correct height.
Maybe you have something that you can use at home.
Otherwise, any DIY store will offer multiple materials that could be used for that.

If you decide to go with an inner liner like “Line-X” (mentioned above), then your feet won’t leave any dents in the floor, since the floor is lined with this very strong material.

Box for Electric Components

I recommend using a box next to the ice bath, where you place all the electronic components mentioned in the components list. 

On the wiring diagram, you can exactly see which components need to go in there.
If you’re going with an ozone generator, then this will be the biggest device that has to go in there.
So by using the dimensions of the ozone generator, it will be easy to judge how big the box should.
If you make a hole on the backside of the box, by drilling or cutting, for example, then you can bring in the cables from the backside of the box, so it looks nice and clean inside.

Note: If you’re using an ozone generator, then you might have to elevate the box a bit, depending on the length of the hose of the ozone generator (as I did in the image below).
The reason for this is simply that the outlet of the ozone generators hose (where the ozone enters the water) should be at least as deep as the lowest point of your filtration pump so that the ozone travels through enough water on its way to the surface.
This, of course, isn’t necessary if the hose is long enough or if you can find a longer one with the correct dimensions at a local hardware store.

Flooring in Front of the Ice Bath

Depending on the location where you’ll place your ice bath, it might make sense to use some form of plates as flooring to put in front of the ice bath. So that you have a place to take off your shoes, so you can jump in with clean feet.
I think it looks nice if these panels are made from the same material as the box for the electronic components, and are of the same length as the freezer. Maybe you can buy both from a local hardware store.

Connecting all the Components

• <g data-name="Layer 2" id="Layer_2"><path d="M20,4V2H18V4H16V7a3,3,0,0,0,2,2.82V16H14V2H2V22H14V18h6V9.82A3,3,0,0,0,22,7V4ZM7,19H5V17H7Zm0-4H5V13H7Zm0-4H5V9H7ZM7,7H5V5H7Zm4,12H9V17h2Zm0-4H9V13h2Zm0-4H9V9h2Zm0-4H9V5h2Z" /></g> Power strip with surge protection and at least 3 sockets (view on Amazon)
• Zip ties (view on Amazon)

If you have all the components prepared, then its time to connect everything together.
 (Note: Usually, it’s recommended to wait for 24h before turning on refrigerators and freezers after transporting them.)
On the wiring diagram below, all the teal lines are the electric cables that you need to plug in.
Marked in grey are all the other components. A detailed description of all steps is just below the diagram.

Steps to connect all components (starting from the power outlet):

1. Plug the GFCI safety adapter directly into the power outlet of your home
2. Place a power strip inside the box and plug it into the GFCI safety switch
3. Plug the power cord of the filtration pump into the power strip
4. Plug the power cord of the ozone generator into the power strip
5. Plug the power cord of the digital temperature controller into the power strip
6. Plug the power cord of the chest freezer into the socket labeled “cooling,” which is attached to the digital temperature controller
7. Use some zip ties to tie the hose of the ozone generator and the cable of the water temperature sensor together with the power cord of the filtration pump. This will leave you with a nice thread that then goes into the chest freezer

Step 3: Using and Maintaining Ice Bath

Filling the Chest Freezer with Water

Where to get the water from?

• Long Garden Hose to Fill and Empty the Ice Bath (view on Amazon)
• If needed: Adapter to Connect Hose to Indoor Sink Faucets (check size & view on Amazon)

If you have a garden hose with a water connection nearby, then this question is already answered.
f you don’t have one nearby, then you can get a connector that you can use to connect a garden hose even to most indoor sink faucets as well.
Just check that the diameter of the adapter matches the one of your faucet and garden hose. 

Leveling the Ice Bath
Every time before you fill-up the ice bath with water, I recommend that you check if it stands firmly with all four corners on the ground.
If your floor is uneven, and one corner of the freezer is always losing contact with the floor, then the weight of the ice bath will not be distributed evenly.
If the freezer is wobbling around, then that can lead to cracks in the material once you fill it up with water.

So check if you have slide something underneath a corner so that it stands firmly on the ground.

How much Water to put in?
How much water exactly to put in is different for every person.
As a guideline: I’m 6 feet (183cm), and 176lbs (80kg), and in my ice bath, the water is filled up to 5 inches (approx. 13cm) from the upper end of the inner walls, when I’m not in the ice bath.

This is a rather high water line, where I need to go in really slowly so that the water doesn’t spill over the edges.

I recommend you simply bring a ruler with you while you’re filling it up, filling in a bit less then I did, then jumping in and then deciding if you want to fill in some more water.

Hygiene

How long the water stays clean is related to how clean you are when getting into the water. If you want to have the water clean for as long as possible, then I recommend only getting in the ice bath after a shower. Sweat, as well as any form of lotion, oil, deodorant or similar product, will impact the water quality.

Additionally, I always make sure that my feet don’t bring in any debris into the ice bath, which can stay on the floor of the ice bath and impact the water quality.
This is where some plates or flooring in front of the freezer comes in handy.
So that you can place your shoes next to them, and get in the tub with clean feet.

Getting inside the Ice Bath

How do you actually enter the ice bath? If you’re similar in height to me (6 feet / 183cm) or taller, then you can easily just hold on to the edges of the bath and step inside.
If you’re smaller, then something small to stand on might be useful.
On the inner side of the ice bath, there’s something that looks like the step of a pool, but that is not what it is. This is where the compressor of the chest freezer is located, so it’s best to avoid stepping on it.

Getting Out of the Ice Bath

When leaving the ice bath, I recommend making sure that there’s no water running down the outsides of the ice bath.
There’s definitely going to be some water drops that will end up on the edges, and ideally, you’ll towel them off before you close the lid.
Otherwise, the edges can start to smell a bit after a couple of weeks.

Changing out the water and cleaning the ice bath

Since we sealed the plug hole, we need another way to get the water out of the pool again.
I recommend the following process.
It involves a couple of different steps, but after doing it once or twice, you’ll be able to do it pretty quickly.

1. Connect your garden hose to your filtration pump
If you got the pump that I recommended in the component’s list, then there’s no adapter necessary. You can simply put any size hose onto the outlet of the pump (the plug gradually increases in width).
Just place the pump on the bottom of the freezer (instead of on the step, where I have it usually placed) and let it pump out all the water.

2. Important: Disconnect the garden hose before the pump starts sucking in air
These pumps usually should not run dry, so make sure to turn off the pump before it’s starts sucking in air. If you don’t want to wait for the moment where the water is so low that you can turn the pump off, then there’s another way to empty the pool:

All you need to do is filling the hose with water, either by sucking the air out or by letting the pump do it. Then, once the hose is filled with water, you just need to make sure that the end of the hose which is outside the pool is placed lower than the end of the hose which is inside the pool. This way, gravity will get out all the water for you. This technique obviously only works once the hose is filled with water already.

To do this, I always place the filtration pump on the floor of the ice bath and place the hose underneath the pump, using the pump as a weight. Then almost all of the water will run out of the pool by itself.

Ice baths can have a positive impact on several aspects of your health.
However, there are many more factors that are critical to reduce chronic disease risk and optimise your health.

Learn how to apply the knowledge of the world’s leading experts on health and longevity to your own life. 
Schedule a free coaching session by clicking the link below.

3. Removing the remaining water with a box

• Plastic Box with Flat Sides to Scoop the Last Bit of Water Out (view on Amazon)

There’s going to be some water left, so you can use a box and scoop it off the floor.
This works surprisingly well, if you are using a square box with flat sides, as the once suggested in the link above.
Obviously it’s not going to work with a round bucket.
With around 10 scoops, I’m getting out almost all the remaining water

4. Using a Bath Towel for the remaining Water
For the remaining little bit of water, you can just place a bath towel on the floor of the pool, which will get all the remaining water right out.

Now that the pool is empty, you can either fill it back up again, or what I recommend:
First scrubbing the walls off with a towel and a natural house-hold disinfectant.

That’s it! Now you know how you can build and operate your own DIY chest freezer ice bath! 
If you have any questions or comments, please let me know in the comment section below!

And if you know somebody who could be interested in building an ice bath, then please consider sharing this article with them.

Make sure you also check out my resource page, which includes lots of other cool tools for living a healthy life.

Happy ice bathing!

– Tobias

Subscribe to Science-Backed Health

Share this post

Comments

[powr-comments id="9ece4bfa_1578822149"]

How often should you change water in ice bath?

How do you disinfect a cold plunge?

How long can you stay in an ice water bath?