Polar Monkeys Star Treatment 2.0 Review

Over the years, I’ve tried ice baths of all shapes and forms, including traditional tubs, inflatables and barrels. And while I appreciate the use cases for all of those, I think there’s just something special about submerging yourself in ice-cold water while remaining upright and on your feet. 

That’s why I was so excited to finally get my hands on the brand-new Star Treatment 2.0 by Polar Monkeys. It’s a beautifully crafted, barrel-style cold plunge made with a stainless steel interior and cedar wood paneling on the outside. 

Here are my key takeaways after testing the unit:

• The 1-horsepower chiller has impressive cooling power and is capable of making ice.
• Despite its strong cooling performance, the chiller is relatively quiet. Unlike other chillers I’ve reviewed, I never felt the urge to turn it off because it was too loud.
• Getting in and out of the tub should be easy for most people, thanks to decent ergonomics and the included step stool. However, if you have mobility issues, it might not be the perfect tub for you.
• The water circulation, filtration and sanitation work well, but I would prefer more water movement to break the skin’s thermal barrier and improve filtration performance.
• The chiller has dual functionality and can actively heat the water to 107°F (41°C), turning the barrel into a hot tub.
• The tub is built to last from premium materials and looks absolutely amazing. I really like the combination of stainless steel on the inside and the cedar wood exterior.
• Priced at just under $7,000, the Star Treatment isn’t exactly cheap. But I think it’s a great value considering the quality of the tub and chiller (especially when compared to plunges from other brands at a similar price point).

Before we jump into the nitty-gritty, it’s worth pointing out that I own the “Residential Pro” model. Polar Monkey also offers a commercial model, which comes with a different chiller that’s designed to work in more demanding situations (like when you have multiple people plunging back to back).

Polar Monkeys Star Treatment 2.0 Hands-On Review

In a nutshell, I really like the Star Treatment 2.0 and have found myself using it consistently after hot sauna sessions. I have access to a handful of plunges that are set up in my backyard for testing, but I keep coming back to the Star Treatment because I find there’s something strangely pleasant about plunging in an upright position.

Of course, there are pros and cons to creating a more “comfortable” environment for cold plunging. If improving your mental resilience is important to you, plunging in the most uncomfortable environment possible is helpful. On the flip side, if you’re struggling with cold exposure and making it slightly more comfortable (or convenient) is the difference between actually doing it (instead of merely thinking about it), then I recommend going the “easier” route.

For example, my wife isn’t quite as enthusiastic about cold plunging as I am, but she still does it on a regular basis because of its many health benefits. However, she “enjoys” cold plunges more when she can remain in an upright position rather than having to lie down in a tub.

Considering her clear preference is for barrels over tubs, we decided to make the Star Treatment 2.0 “her” plunge (so this article incorporates her feedback as well as mine).

For my pre-workout plunges, I like to make the experience as uncomfortable as possible to reap the maximum benefits. In other words, I usually jump into one of my tubs that keeps the water right at the freezing point. 

For my post-sauna cold plunge sessions in the evening, I prefer the Star Treatment 2.0 because it’s closer to the sauna and it mimics the Arctic plunge experience we had during a recent trip to Norway.

I should also point out that before our Norway trip, we kept the Star Treatment’s chiller set to 48 to 55 degrees to accommodate my wife. But since that trip, she now plunges in ice water. As a result, we no longer keep the Star Treatment set to a higher temperature. Still, the combination of being in an upright (and more controlled) position and shorter plunge duration helps facilitate a better nervous system response, which is conducive to better sleep.

In other words, it doesn’t rev me up too much.

Here are some key details about the unit’s performance and technical specs:

Barrel size: The stainless steel barrel is about 44 inches tall and 34 inches in diameter, holding about 120 gallons of water. That’s large enough to allow most plungers to submerge themselves up to the chin. Depending on how tall you are, you can even submerge your head by squatting down or hinging forward. For reference, I’m six feet tall and weigh about 215 pounds and I have no problems fully submerging myself in the water.

Ergonomics: The barrel has a built-in step/seat on the inside which, together with the heavy-duty step stool on the outside, makes it relatively easy to get in and out. Depending on how much water you add to the barrel, you can use the seat on the inside to fully sit down and relax. Our barrel has so much water that I barely touch the seat with my butt. Instead, I just float in a comfortable half-squat.

Cooling power: The residential chiller that comes with the barrel is surprisingly powerful and can even make ice — albeit only a relatively thin layer on the water’s surface (as shown in the short video clip below). I’ve never tested an external chiller that can actually make ice, so that’s an impressive feat.

Filtration system: The Polar Monkeys chiller uses a combination of sediment filtration and ozone to keep the water clean and sanitary. However, considering the relatively large water volume and the limited flow rate of the water pump, you’ll likely still need to use non-toxic water treatment options – especially if you maintain higher water temperatures (such as around 40 degrees).

Why Barrel-Style Plunges Are a Game-Changer

At 44 inches, the Star Treatment 2.0 is relatively tall (and taller than both the Ice Barrel 400 and 500). That’s great because it means it’s easier to submerge your entire body in the water, especially if you’re tall. The downside of the tall barrel is that it might be more challenging to get in and out if you’re of smaller stature. 

My wife is 4’11” and has to rely on her upper body strength to get in and out of the barrel, considering how low the step on the inside of the barrel is.

While I was reviewing the Ice Barrel 500 (which also has a seat/step on the inside), I noticed that it was so high up that it was almost impossible to submerge my head in cold water — something I like to do because it really triggers my fight or flight mode. With the Star Treatment 2.0, I love that I don’t have that issue. 

On the other hand, my wife prefers the height of the Ice Barrel’s interior step because she is much shorter than I am.

As I alluded to in the intro, there are pros and cons to maintaining an upright vs inclined position during cold water immersion. Perception and personal preferences play a role too. To me, being reclined feels more vulnerable and I consider it more challenging. If that’s the same for you, I’d argue that doing something that’s more challenging helps build mental resilience. 

On the other hand, if you’re on the fence about cold plunging and using a barrel-style plunge set to 45-55 F is the only way to make you jump in regularly, go for it. If you stick with it you’ll likely adapt to the cold so well that it won’t matter what temperature the water is or what shape the tub is. So, don’t get too hung up on such details and, instead, focus on jumping into the water regularly.

Powerful Cooling, Heating and Filtration Performance

Arguably, the standout feature of the Star Treatment 2.0 is the ability to make ice – something most external chillers can’t do. In fact, all the other external chillers I have owned over the years topped out at 37 degrees. 

But there’s a catch. When the chiller is making ice, its water filtration capability is reduced so as to not damage the pump. After all, the pump can’t circulate ice and wasn’t designed to run dry. While in ice-making mode, the chiller continuously cycles between making ice and thawing it, and water filtration kicks back in during the thawing cycle. 

While I do enjoy jumping into water with ice floating around me, I’m not 100% convinced that doing so offers measurable health benefits compared to water that’s a few degrees warmer. As a result, I kept my chiller set to 35 during testing, which is just above the freezing point and doesn’t impact water filtration performance.

However, it’s worth pointing out that even though the chiller circulates less water volume in ice-making mode, water quality isn’t negatively impacted much because bacteria and other pathogens don’t grow in near-freezing temperatures. In other words, ice-making mode mainly affects sediment filtration performance.

It’s also worth mentioning that the Polar Monkeys chiller can actively heat water to 107 degrees. In fact, any time you change the temperature setting on the chiller to a value above the current water temperature, the chiller’s heater kicks in to warm the water. That’s different from other chillers I’ve tried in the past, which don’t actively heat the water. Instead, they just turn off the compressor until the water naturally warms up (assuming the ambient temperatures are above the current water temperature).

Much like the ability to make ice, I think the hot tub feature is not incredibly useful for most people because changing the water temperature from 35 degrees to 107 degrees (or vice versa) takes a long time. In other words, you’d have to let the chiller run overnight to change from cold to hot. That’s impractical and consumes significant energy. 

Of course, the heating feature is an attractive option if you want to use the Star Treatment as a hot tub exclusively, or if you want to switch functions depending on the season.

But if you’re in the market for a hot tub, you’ll likely prefer a tub that fits more than one person. And to really leverage the health benefits of ice bathing, you need to do it consistently. 

Design That Combines Durability and Style

I love how the Star Treatment 2.0 looks (and feels). I’ve owned and reviewed my fair share of (inflatable) plastic tubs — including the Plunge Air, the Therafrost and the Inergize — but I’ve always preferred stainless steel and wood options. 

The Star Treatment 2.0 features a combination of a stainless steel drum that’ll last essentially forever (and is easy to clean) with a sleek cedar wood exterior that holds up to the elements (and which looks and smells great). 

I also appreciate the relatively small footprint of the barrel and chiller. I review a lot of cold plunges, saunas and other gadgets, and space is always a consideration. The Star Treatment requires only minimal floor space while offering ample room on the inside.

Overall, this plunge fits great on our patio and it blends right in with our two saunas.

Quiet Operation

One of the things I didn’t like about the Evolve Standard chiller that came with my Plunge Air was the loud noise the chiller would make. It was so loud that I regularly turned it off, especially when we were having dinner outside on the patio (next to the chiller).

I’m thrilled to report the Polar Monkeys chiller is relatively quiet and I never feel the urge to turn it off!

Intuitive Controls

Polar Monkeys offers two ways to control the chiller (i.e., changing the temperature, turning the unit on and off, or changing the ozone sanitation settings), including an on-screen display and a mobile app.

The quickest way to change settings on the chiller is via the bright touchscreen on the front of the unit.

Note that I emphasized “bright.” I’m pointing this out because some of the chiller screens I’ve come across in the past were so dim that they were almost impossible to operate in daylight. The screen on the Polar Monkeys chiller is incredibly bright, which seems like an obvious design decision but nonetheless makes it stand out from the competition.

The only thing I don’t like about the touchscreen is that it automatically locks (to prevent accidental changes) after a short period. Unlocking the screen requires the simultaneous push of two buttons for several seconds, which isn’t a big deal. However, I’m usually in a rush and would prefer being able to turn the unit on or off, or change the temperature, without delay.

The second way to control the chiller is via the Tuya mobile app (the same app you can use with the Therafrost and Inergize chillers). Before you can control the chiller via the app, you have to hook it up to the chiller via WiFi. 

It’s worth noting that you can use the app to automatically turn the chiller on and off based on a set schedule. In winter, I usually use that scheduling feature to turn the chiller off at night and back on in the morning. Doing so improves energy efficiency (we run on batteries at night and on solar during the day) and doesn’t significantly impact water temperature or quality.

Low Ongoing Maintenance Requirements

Thanks to its powerful chiller, the Star Treatment 2.0 requires relatively little ongoing maintenance. Every two weeks, I check on the sediment filter and test the water quality. If necessary, I pour in two tablespoons of the hydrogen peroxide that comes with Polar Monkey’s water maintenance package. Approximately, every four weeks, I replace the sediment filter to ensure consistently high water flow. 

I can tell when the sediment filter needs to be replaced based on how dirty it looks, as well as by checking the flow rate displayed on the chiller. Anything below 15 liters per minute is a good indication that the pre-filter or sediment filter has to be cleaned or replaced. 

I also use a skimmer to remove any debris that’s floating inside the tub, which usually includes dust and pieces of wood chips we might have accidentally dragged in.

Every couple of months, I drain the barrel and refill it with filtered water. We now have a whole-house water filtration system that removes chlorine and other chemicals from the water. Before we installed that system, we used an activated charcoal filter I could attach to a garden hose to refill our plunges.

Easy Setup

Setting up the Star Treatment cold plunge barrel takes less than 15 minutes (not accounting for the time it takes to fill the barrel with water) and consists of the following steps:

• Connecting the chiller to the barrel using the supplied hoses and fittings. I recommend using the included Teflon tape around the fittings to prevent water leakage.
• Installing the pre-filter and sediment filter to the back of the chiller.
• Filling the tub with water before turning on the chiller.
• Optional: Connecting the chiller to WiFi using the Tuya app.

Once you’ve set everything up, check all fittings and connections for leaks to tighten them up, if necessary.

What I Would Improve

During my testing over the past several weeks, I’ve come across a couple of minor issues that are worth pointing out:

1. Condensation. Depending on the ambient temperature, you can expect some condensation around the hoses and around the internal components of the chiller (e.g., the water pump). The condensation is likely not an issue when you use the plunge outside on a surface that can handle water (such as concrete). However, if you operate the unit inside (like in your garage), I recommend investing in a drip tray or floor cover that can safely absorb the condensation. I should also point out that my contact at Polar Monkeys indicated that they’re working on covers or insulation around the hoses to mitigate that issue in the future.
2. Warping lid. Polar Monkeys accidentally sent me an old wooden lid with my Star Treatment 2.0, which started warping with changes in temperature and humidity. Rest assured, when you order the new Star Treatment 2.0, you’ll receive the new insulated lid (which I should be getting in the near future).

I’ll make sure to update this article should I run into any issues over the next few months.

Is It Worth the Price Tag?

The Star Treatment 2.0 isn’t cheap, but I think it’s worth the nearly $7,000 price tag if you consider the powerful chiller it comes with, the premium materials (i.e., the tub will likely last you forever), and how little time and money you need to spend on keeping the water clean and sanitary.

For comparison, many of the premium inflatable plunges I’ve reviewed retail for between $4,000 and $5,000, while the stainless steel Sun Home Saunas Cold Pro costs over $9,000. The Star Treatment 2.0 sits smack in the middle and offers many of the benefits of much higher-priced options.

Shop Star Treatment 2.0

Be sure to use the discount code MICHAEL for $200 off your Polar Monkeys purchase.

Polar Monkeys offers a 30-day return policy (subject to a 25% restocking fee) and a 12-month warranty against defects in materials and workmanship. Return shipping is covered by Polar Monkeys within the continental United States.

Final Verdict: The Star Treatment 2.0 Is the Best Cold Plunge Barrel I’ve Tested

I consider the Star Treatment 2.0 the best cold plunge barrel I’ve ever tested. I also like it much better than any other tub-style plunge in its price range. I just love the combination of stainless steel and cedar wood, paired with a powerful chiller that can make ice (even though I don’t think you should use it for that in the interest of prolonging the lifespan of its components).

The only two plunges I’ve tried that I like better are the Sun Home Saunas Cold Plunge Pro and the Morozko Forge. But those are significantly more expensive, take up much more floor/ground space, and provide a totally different (reclined) plunging experience.

So who is the Star Treatment 2.0 for? I’d argue it’s the best plunge for anyone who wants to take cold water immersion seriously, is looking for an upright tub that looks good and will last forever, and who doesn’t want to spend a lot of time on ongoing water maintenance. If that’s you, look no further than the Star Treatment 2.0.

Cold plunging has revolutionized how I recover and recharge, and the Polar Monkeys Star Treatment 2.0 has become an integral part of my routine. I love jumping into the barrel for a quick dip after an intense sauna session in the evening because the combination of sitting upright and slightly warmer water feels more comfortable and doesn’t trigger the same intense fight-or-flight response I get from a tub. 

Whether you’re a seasoned enthusiast or just starting your journey, this plunge offers unparalleled quality and experience. I’d love to hear about your cold plunge journey – share your thoughts in the comments below!

Michael Kummer

Michael Kummer is a healthy living enthusiast and CrossFit athlete whose goal is to help people achieve optimal health by bridging the gap between ancestral living and the demands of modern society.