Ditch the wire brush. We put a few self-cleaning water bottles to the test.
Updated Jan. 29, 2024 1:00 p.m. PT Sterilizer Uv
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Whether I'm at home or on the go, I have trouble staying hydrated throughout the day. See, I'm a work-from-home employee, but my remote work doesn't stop me from getting out and seeing the sights. I love to stay active. And with any healthy lifestyle, drinking enough water is crucial. The key thing that's helped me stay hydrated is a great reusable (and refillable) water bottle. And as an added benefit, reusable water bottles lower the use of plastics and have a positive impact on the environment.
There is a downside here, however: You'll need to keep that water bottle clean. After all, you don't want your bottle to become a safe haven for bacteria. Many reusable water bottles are dishwasher safe, so tossing it in for a clean now and then can help. However, there's a better method to ensuring your drinking water is always fresh and clean and that's by using a self-cleaning water bottle. Obviously, self-cleaning water bottles take the responsibility of cleaning out of your hands. And, more notably, it makes sure that the water you drink is free of impurities.
From left: The CrazyCap, Mahaton and Larq bottles all sanitize themselves with UV-C light.
Self-cleaning water bottles use UV technology to zap waterborne microbes and keep them out of your drink, regardless of the water source. This is unlike filtered water bottles, which use a variety of mechanisms to trap pathogens and sediment.
The biggest difference between water bottles that provide filtration and self-cleaning water bottles is that the UV technology used in self-cleaning bottles doesn't get rid of dirt and sediment. So while the bottles can kill viruses, bacteria and other microorganisms that can make you sick, they won't filter out heavy metals or other particulates like an actual purification system might. They're still better at ensuring you have clean water than traditional water dispensers or single-use plastic bottles, though.
Because of that, I decided not to test these self-cleaning water bottles outdoors. Instead, I used tap water to find out which self-cleaning bottles lived up to their claims. I also did most of my water drinking at home or in the office. So which is the best self-cleaning water bottle? You'll find my thoughts below. Ditch your plastic water bottle and start drinking from almost any water source with reckless abandon using your own personal water purification system.
The CrazyCap bottle has two water purification modes: normal mode and "crazy mode." According to CrazyCap, normal mode kills up to 99.99% of contaminants and is suitable for "low to medium contamination," such as from public water fountains and tap faucets. Crazy mode, on the other hand, kills up to 99.9996% of contaminants and is suitable for "medium to high contamination," such as from lakes and rivers. The normal purification cycle takes 60 seconds and the crazy purification cycle takes two and a half minutes.
The CrazyCap also has an autoclean function, which turns on six times per day for 20 seconds. CrazyCap says this periodical exposure to UV-C light prevents microbial growth and odor, and it seems to work: After three days of use, I didn't notice any smells or films inside the bottle. Additionally, purified water from the CrazyCap bottle tasted significantly better than water from the tap faucet.
The CrazyCap bottle is more slender than the others on this list, which I liked. It fits into my car cup holders, as well as the mesh cup holders on my gym bag and backpack. It's a bit taller than the Larq and the Mahaton, so you might have trouble fitting it in the top rack of your dishwasher.
Personally, I think the best thing about CrazyCap is that you can buy just the cap, which according to the website fits on many different water bottles, maybe something you already have.
On a single filtered water bottle charge, the CrazyCap will last up to two months, but only if you leave it to autoclean. Manually starting the self-cleaning water bottle purification cycle affects that charge time, though CrazyCap doesn't specify by how much.
The Larq bottle also has two purification modes: normal and adventure. Normal mode purifies up to 99.99% of pathogens in 60 seconds, and adventure mode purifies up to 99.9999% of water in three minutes. It doesn't seem like much of a difference, but that 0.0099% water filtration can make or break water that comes from a stream or other natural source.
You can activate the UV-C purification light whenever you want by pressing the button on the top of the bottle, but Larq also comes to life every two hours for a 10-second cleaning cycle. I didn't notice any funky smells or films on the inside of the Larq bottle after three days of constant use of the self-cleaning bottle.
Larq was the only one of the three bottles that didn't taste significantly better than my water, however. It tasted slightly cleaner, but I probably couldn't tell the difference if someone blind taste-tested me.
The Larq bottle is made of vacuum-insulated stainless steel and keeps your safe drinking water at a cold temperature for up to 24 hours. It's sleek and aesthetically appealing -- my only complaint was that there's no groove or curve to fit your hand. You could always purchase the handy travel sleeve to solve that problem.
A single charge on the Larq can give you up to two full months of use, assuming you send it through three to four cleaning cycles (in normal mode) per day. If you use adventure mode, the charge will last up to 12 days.
Truthfully, all three of these water bottles did a great job at keeping themselves clean. After three days of drinking and constant refills and no hand-washing, none of these bottles smelled musty or had any sort of film on the inside, two things my normal steel bottle often produces.
The Larq, CrazyCap and Mahaton all use UV-C light to zap all of the major waterborne pathogens; they're all stainless steel water bottle options (no cheap plastic water bottles here), and all these best self-cleaning bottle choices have automatic cleaning cycles. On top of that, all three are easy to use and they all have battery notifications so they'll never die without warning.
I had virtually no complaints about any of these self-cleaning bottles, and if you're looking for an aesthetically pleasing bottle that purifies your water, any of the three will get the job done.
The only major difference between the three? The Larq and the CrazyCap both have two modes, while the Mahaton only has one. If you plan on using your self-cleaning water bottle with outdoor sources of water, you may want to opt for the Larq or the CrazyCap since they have overdrive modes that kill even more microorganisms.
Self-cleaning water bottles use UV-C light to kill bacteria, viruses, protozoa and other microorganisms by destroying their DNA. The UV light sterilizes both the water in the bottle and the interior surface of the bottle.
UV-C light serves as a convenient, mostly hands-off way to keep reusable water bottles clean without the need for chemicals or soap. Most self-cleaning water bottles, including the three covered in this article, also have all the features you'd look for in a normal reusable water bottle: They keep steaming hot water hot and cold water cold (or room temperature water at room temperature), and they're durable.
I tested three UV-powered self-sanitizing water bottles -- the Larq bottle , the CrazyCap bottle and the Mahaton bottle (which is on Kickstarter, but is fully funded and already shipping products) -- using the tap water from my apartment's kitchen sink (my preferred water source).
I usually don't buy bottled water, and I don't have a faucet water filter, so I often drink this water unaltered. I thoroughly cleaned each bottle and charged them overnight to ensure they were ready for testing. Then, I used each bottle for three days in place of my normal reusable bottle.
You should consider six important factors when choosing a UV-powered water bottle: Purification, taste, design, ease of use, capacity and battery life. If you decide to purchase a self-cleaning water bottle, you'll want one that kills as many microbes as possible, produces a good taste, is easy to hold and transport, and lasts for a decent period of time on one charge.
1. Purification: What does the bottle promise to get rid of, and at what percentage? Also, how long does it take for the bottle to purify the water? Is there an auto-clean function? I also considered how the bottle smelled and looked on the inside after three days of use.
2. Taste: How does the water taste after going through the purification cycle, compared to my drinking water?
3. Design: What is the bottle made of and how convenient and easy is it to carry around? Does it keep water cold?
4. Ease of use: How easy is it to set up the bottle for first use, clean it and store it?
5. Capacity: How much water does the bottle hold? Will you be refilling it constantly, or will the pure water last you a while?
Water Treatment Systems 6. Battery life: How long does the bottle last (and how many cleaning cycles can it complete) on a full charge?