I love my Hydro Flasks. I take them with me to the beach, the gym, rock climbing, bushwalking…pretty much an adventure I go on my Hydro Flask comes with me.
One of my favorite weekend activities is bush walking with my kids and exploring waterfalls and swimming holes. One of the downsides of being a sinlge dad and bush walking with kids is you have to carry a lot of supplies and A LOT of water. And water is heavy!
So when the company Waatr reached out to me about reviewing their new HydroCap product that sterilizes water (including river water) I jumped at the opportunity to give it a go.
The HydroCap is lid that produces UV-C light to kill over 99.9% of bacteria, protozoa and viruses in water, making it safe to drink. It conveniently fits on any wide mouth Hydro Flask bottle as well as a variety of other brands such as Klean Kanteen and Simple Modern.
NOTE: Waatr sponsored me to write a post of my choosing about their product. I chose to write this review as I actually use and love this product, but as always, take my opinion with a grain of salt and do your own research before buying.
Drink Water (Almost) Anywhere By Killing Over 99.9% of Bacteria, Protozoa and Viruses
One of the dangers of drinking water from unknown sources or of unknown quality is that they may contain bacteria, protozoa or viruses that can make you sick and cause disease.
While the water may appear clear you never know what is upstream or what dangerous microscopic organisms may be in the water. This can apply to tap water as well in some areas.
What the HydroCap does is it actively kills 99+% of these microorganism rendering them inert and unable to multiply in your body which can cause you to get sick.
The HydroCap uses the same technology as the original CrazyCap and below you can see a graph of just how effective the CrazyCap was as killing e.coli bacteria.
A similar study was done on the HydroCap to test it's effectiveness against e.coli and below you can see the final report for this test:
When the viruses, bacteria and protozoa are exposed to UV light the proteins present on the cell wall ruptures and this causes them to die.
This effect is enhanced even further when cells stop replicating as genetic material (RNA and DNA) and form thymine dimers upon absorptions of UV light (according to Waatr).
How Exactly Does The HydroCap Work To Kill Bacteria and Viruses?
The HydroCap takes the worry out of your water by using 2 x 20mW UV-C LEDs for maximum purification against bio-contaminants.
UV-C light has been shown to have maximum germicidal efficacy. This means the lights can be powered by a small lithium ion battery in the lid yet still achieving great results.
The UV-C lights shine into the water and kill bacteria, protozoa and viruses. I personally make sure to not overfill my bottle so that all water is exposes to the UV light and none of it is missed.
It's also advised that you shake or swirl the bottle during the cleansing process to ensure full efficacy.
The longer the UV light shines on the micro-organisms the more likely they are to die. This is why a 3 minute cycle is advised for more questionable water sources.
You can activate a 1 minute cycle designed for already clean tap water, by simply pressing the top button twice to activate.
You can activate a more intense 3 minute cycle that is designed for more questionable water sources – such as drinking directly from a river or a lake – by pressing the top button 3 times. This is the cycle I used and I used it twice just to feel completely confident any bugs that could make me sick were dead.
The top of the HydroCap will pulse blue while it is active and then will quickly flash green once the cleaning cycle is complete.
It only works effectively in clear water, where the UV-C light can shoot all the way down to the bottom without being obscured or blocked off by sediments in the water.
Price of The HydroCap + Options
Currently the HydroCap is available directly from Amazon or Waatr's website and retails for around $99.
It doesn't come with a bottle, however it fits on all wide mouth Hydro Flasks as well as many other brands mentioned below.
The brand Waatr also sells the successful CrazyCap lid and bottle and they have a new PureMax 4D lid and bottle which used 2 x UV-C lights just like the HydroCap but it also has a charcoal and ion-exchange filtration system to reduce particulates, chemicals and metal contaminants.
Fits Easily On Your Hydro Flask Or Other Popular Bottles
This is what drew me mostly to the HydroCap. I already own multiple Hydro Flask bottles and I absolutely love them.
The fact that I don't need to buy a new water bottle and I can use it with the existing water bottle that I love is a huge plus for me. You just need to make sure you have the wide mouth Hydro Flask not the original
Below is a full list of the brands and bottles that the HydroCap fits on:
HydroFlask Wide Mouth Bottles – 12, 16, 20, 24 trail, 32, 40, 64 oz
Simple Modern Summit – 10, 14, 18, 22, 32, 40, 64, 84, 128 oz
Takeya – 14, 18, 24, 32, 40, 64 oz
Mira – 12, 18, 22, 32, 40 oz
Klean Kanteen (Wide Mouth) – 12, 16, 20, 27, 40, 64 oz
Fifty/Fifty – 10, 16, 18, 20, 40 oz
Hydro Cell – 18, 24, 32, 40 oz
Thermoflask – 14, 18, 24, 32, 40, 64 oz
Gold Armour – 14, 18, 24, 40, 64 oz
Iron Flask – 18, 22, 32, 40, 64 oz
Kills Protozoa + Viruses That Other Filters Struggle To Filter Out
One of the major benefits of the HydroCap over other filters like the LifeStraw and other membrane microfilters is that these filters often don't filter out viruses. They'll filter out bacteria, micro-plastics, sediments and parasites but they will let viruses pass through and some let protozoa pass through also.
This means the water could still pose a threat of disease.
The UV light from HydroCap, however, will kill both viruses and protozoa as well as bacteria – making it one of the most effective forms of creating clear water on the go.
With the HydroCap you can be confident that 99.9+% of viruses will be killed and unable to make you sick.
Only Works With Clear Water
One of the major considerations with the HydroCap is that it only works in clear water and won't work in murky water.
This is because UV light is much like visible light in that it can't travel through opaque objects. So if the water is murky the UV light won't reach the bottom of the water and won't be able to kill all the micro-organisms in the water.
This means you'll want to use the HydroCap with clear water sources only, which does limit it's use in some survival situations.
For me this is fine. The water I am drinking is from fresh flowing rivers and streams and it only contains minor coloration and minor sediments.
Doesn't Filter Sediments, Salts, Minerals, Micro Plastics Or Other Harmful Chemicals From Your Water
The HydroCap doesn't “filter” your water and by that I mean it doesn't capture or remove anything from your water.
It simply uses UV light to shine into your water to kill the microorganisms in your water. But it won't take anything out of your water.
This is where membrane microfilters are more effective because they can actually remove sediments like sand and dirt and can also remove items like micro-plastic in the water and some other harmful chemicals like heavy metals.
While you can use a product like the Lifestraw to drink from a muddy puddle this isn't something you can do with the HydroCap.
If you want to be able to drink from murky water sources then check out my article on the best Hydro Flask Filters.
HydroCap Doesn't Add Any Chemicals To Your Water
One of the ways to kill bacteria, protozoa and viruses in water is to use purification tablets which tend to use ingredients like chlorine, chlorine dioxide or iodine. This deactivates the microorganisms rendering them harmless and safe to drink.
However, I personally want to avoid adding chemicals into my water wherever possible. In fact, a lot of people buy filters in order to avoid or get rid of chemicals that are added to water so they can drink the cleanest and ideally healthiest water possible.
One of the things I love about the HydroCap is that it doesn't add any chemicals to my water. It uses to UV light to effectively do the same thing as the purification chemicals do while leaving the water as pure as possible.
Doesn't Need To Be Regularly Replaced + Backed By a 10 Year Warranty
When using a membrane microfilter like the Lifestraw or other products these have a limited lifespan. On the upper end they can filter around 1,000-2,000 gallons (3,800-7,500 L) before they need to be replaced and on the lower end you'll get 100-200 gallons (380-750 L) before they need to be replaced…at a decent cost.
Some of them also have timespans of around 3-4 months before they need to be replaced. At $10-$30 each for many of these filters the cost of these quickly surpasses the cost of the HydroCap.
The HydroCap comes with a 10 year warranty and they claim this gives it 16,000 gallons (72,700 L) of filtration over it's lifetime.
If I was to fill up my 32 oz Hydro Flask water bottle 5 times per day and treat it each time I could do this every day for nearly 40 years before I'd reach the 16,000 gallon threshold.
However, lithium ion batteries do deteriorate over a 18-36 month period (as you are likely aware of through your mobile phone draining battery quicker over time) so I foresee the HydroCap to struggle to maintain charge in 10 years time.
However, it uses a very low amount of power to run the UV LED lights so who knows maybe it'll still be working fine in 5-10 years. Only time will tell for that one.
Extremely Simple and Easy To Use
The HydroCap is really easy to use. It's so easy even my kids can do it.
Fill up your water bottle 80-90% full. Here you want to just make sure no water is higher than the level of the UV lights which protrude down into the bottle.
Double tap the top button for tap water or triple tap it for clean river water and the HydroCap does it's just and kills the bacteria and viruses in your water without you having to really do anything.
It's stupidly simple.
Other than shaking or swirling the water around during the cleaning process no effort is required like some filtration bottles require. Plus if you're worried running a second or third cycle is really simple to do.
Self Cleaning Mode
The HydroCap also comes with a “self cleaning mode” that'll keep your bottle clean throughout the day.
Press the top button 5 times to activate self cleaning mode and every hour the lights will activate for 15 seconds to keep your water and your bottle clean from bacteria or other microorganisms growing.
I personally don't use this because each time I fill up my bottle I run a 1 or 3 minute cycle and I still prefer to wash my Hydro Flask on a regular basis to keep it clean. Click here for tips on how to wash a Hydro Flask properly.
Easy Carry Handle
The HydroCap has a high handle that I can easily fit 3 fingers in making it simple and easy to carry.
The handle is rounded and feels comfortable on my fingers and doesn't dig into them in any uncomfortable way.
The handle does permanently stick up, which adds to the size of the lid compared to the regular Hydro Flask lid where the handle rotates down and tucks away. So if you're very limited on space this may be a consideration.
UV-C Safety Sensor So You Don't Expose Yourself To UV Radiation
The HydroCap has a safety system where it will turn off when not attached to your water bottle.
This stops it from running outside of your bottle and potentially exposing yourself to UV radiation unnecessarily. I really appreciate this feature because I have kids who like to play with things that have buttons and lights (they all fight over who gets to press the button when we are treating water on our bush walks).
This feature keeps me and my kids safe. If you have any concerns about the safety of the HydroCap or UV light water bottles in general check out my article on whether or not UV light bottles are safe.
Rechargeable With a Good Battery Life + Waterproof
The Waatr HydroCap comes with a magnetic recharger which clips onto the lid.
The charger is a little bit finicky and can fall off easily so you need to make sure not to bump it while it's charging but overall it's pretty easy to use and the design of it means the lid is completely waterproof.
The battery lasts quite a long time too. You can run the full 3 minute cycle 5 times per day and have self cleaning on and the battery will last around a week.
If you press the top button once it will light up and show you how charged it is:
Green: >40% battery remaining
Orange: 10-40% battery remaining
Red: <10% battery remaining
I'm yet to have it go orange as it's pretty easy to recharge it every couple of days when I'm at home and not using it. I can only see you maybe getting low on charge if you're hiking for days at a time and have no way to recharge it on your hike.
Great Value For Money
Overall I think the HydroCap offers great value for money.
It has allowed me to go bushwalking with my kids and rather than carrying a full gallon of water (3-4L) I can get away with carrying just 32 oz (1 L) and then fill up at the river, treat the water and drink from the river.
For the convenience this gives me plus the ability to also treat tap water, which is great when filling up my bottle from public places, this makes the HydroCap a very versatile lid and it has now replaced my regular HydroFlask lid as my go to water bottle lid.
Backed by a 10 year warranty and able to filter water for years and years I honestly believe this is great value for money and I'll be using this product for years to come.
You can check it out at Amazon or at Waatr's website through my affiliate links below: