how we get squeaky clean water on our sailboat

Off-Grid Boat Life: How We Purify Water

Sometimes we get super sketchy water and sometimes our storage tanks get a bit slimy.  But, we drink it anyway!  After we purify it of course.

Water is our most important resource…we literally can’t survive without it.

The average human should consume 2 liters of water per day.  Here in the tropics, we probably sweat at least 4 liters a day, so we consume more!  At least 65 liters a week between the two of us.

After nine years of living off the grid, we like to think we have the water situation down pat.  Not only can we stretch a gallon of water like a desert rat…we’ve never had to buy bottled water for our traveling home.  This is why we’re sharing the scoop on how we store, filter, and purify our water.

Join us aboard Curiosity for some high-quality H20!

Last time we talked about how we get water on our sailboat: rain collection, public sources, and our best friend Mr. Watermaker.  If you haven’t seen it yet, go check it out.

Water Storage & Why It’s Sketchy

Every boat, RV, tiny home, or whatever form of traveling off the grid home, will be a little different but in general, we all have some sort of storage tank and a method to get it out of the tank.  Either by gravity flow, foot pump, or electric pump.

We have 2 x 100-gallon (378 liters) tanks and an electric water pump that sends water to all the various parts of our boat (sinks, showers, and such).

While our watermaker is our main source of water and the quality is unbeatable, there are instances where we need to source it elsewhere.  Because our watermaker is older, we’ve had a couple of parts burn out on us.  Then there have been times where we’ve been anchored near or in a river where water quality is so dirty and silty, it would have clogged our watermaker filters in no time.

But, no matter where we source our water from, it’s always stored in our potentially sketchy (petri dish in waiting) water tanks.  Even if the water going in is super squeaky clean (like from our RO)…water tanks get grubby!  Here’s why:

  • Our tanks are not perfectly sealed and are subject to whatever bacteria/creatures are in the air or can squeeze through any gaps or seals.
  • It gets hot and bacteria love warm environments.
  • Tanks get exposed to air and outside contaminants each time we open them.
  • Sometimes we fill our tanks with public water (each has its own set of bacteria and unknown quality).
  • Our water tanks are hard to clean and sanitize (most are).

Drinking sketchy water can mean consequences far worse than a dose of Montezuma’s Revenge.  This brings us to the importance of water filtration and purification.


Water Filtration

Carbon (and Brita-type) filters don’t purify water, they filter it.  They help with odor, taste, and remove chemicals (like chlorine) and hard metals (like lead), and sediment.  Which is great!  But, any biological creatures such as giardia or e. coli pass right through.  So, you still have those pesky illness-causing microorganisms to worry about.

Purification is the only way to guarantee safe drinking water but…filters have their place too.  Filters help with particles and taste, which is why we use carbon filters for the “whole house” and all the benefits they provide.

Whole House Filter 

  • Filters and reduces sediment, dirt, sand, silt, rust, scale particles, Chlorine taste & odor, VOC’s

Inline Filter For Water hose


Purifying water

There are lots of ways to go about purifying water (new gadgets hitting the outdoor lovers market all the time).  But for sanity and time’s sake, we’ll stick to the basics…and our fave high-tech method aboard curiosity.

Boiling It

Boiling water is always an option.  Just bring it to a rolling boil for at least one minute.  Simple, effective, no chemicals needed!

Chemically treat it

Iodine is often more effective than chlorine, but iodine-treated water shouldn’t be used for more than a few months at a time. Iodine can be bad for pregnant women and people with thyroid conditions.  This is NOT a long-term option.

Chlorine isn’t great either.  Lots of off-the-grid peeps use chlorine to keep the gunk from growing and purify the water (straight up, not scented, check for recommendations on dilution).  It can do the trick, but…

  • Chlorine is a contaminant
  • makes the water smell like chlorine
  • tastes bad
  • can cause problems with cooking (kills cultures in bread and yogurt)
  • can damage watermaker membranes
  • toxic to fish, other aquatic animals, reptiles, and amphibians

Plus, states, “Drinking water disinfection is essential and saves lives from microbial diseases. But when chlorine and other disinfectants react with plant and animal waste in the water, harmful disinfection byproducts are formed.”



The Ultimate, tech-loving, safety joe approved water purification method is LED-UV.

We’re not talking about the old UV lights that were made with mercury, were power-hungry and needed replacing every year.

There is a new generation of LED-UV and it’s a massive improvement!  As with other LED lights, the LED-UV lights are much more environmentally friendly and last way, way, way longer.

Ultraviolet water purification is the most effective method for disinfecting bacteria from the water (aside from RO). UV rays penetrate harmful pathogens in the water and annihilate illness-causing microorganisms by attacking their DNA. 99.9% of bacteria, viruses and other pathogens…dead!

As with other LED lights, the LED-UV lights are much more environmentally friendly and last way longer (around 8-10 years).

  • Sterilizes 99.9% of bacteria, viruses and other pathogens
  • Improves taste, odor and color
  • Chemical-free
  • Low power consumption
  • Hooks up to a standard 12V battery or AC power


Acuva has offered up 10% OFF any system! We have the Arrow 5 and we installed the Arrow 2 on Jason’s mom’s van.

Re-Mineralize Filter

 iSpring 10″ Inline Minerals Filter FX15

This alkaline antioxidant filter provides abundant active hydrogen. It also increases the reduction of power by increasing pH, making small water clusters, and providing beneficial minerals such as calcium, magnesium, potassium, and sodium.


best water purification for off grid sailboat

Show Me The Money – The Most Affordable Option

Remember when we said the average human should consume 2 liters of water per day?  Well, that is just the bare minimum.  Here in Tahiti, a 5-liter jug is 330 CFP.

  • 2 liters a day per person x 365 days in a year = 730 liters
  • That means we would need 146 of those 5-liter jugs.
  • 146  5-liter jugs x 330 CFP Franc = 48,180
  • 1 CFP Franc = 0.0095 USD
  • 48,180 CFP = $457.72 USD
  • $457.72 A Year Per Person x two = $915.44

$915.44 a year just in drinking water!  The Acuva Eco and a couple of charcoal filters may seem like a big upfront investment, but it is way cheaper than buying bottled water.

Big Takeaway

Water filtration and purification are incredibly important to any traveler and especially anyone traveling with their home.

We have filled our tanks with all sorts of sketchy water sources that are not advised for drinking.  But, because we have our filters and LED-UV for purification…we’re able to turn any water into squeaky clean, high-quality H20!  Water quality so good, it’s better than bottled water.

We have two thirsty felines on board and have friends, family, and patrons who come stay with us.  So, having an onboard setup as we do…well, I couldn’t imagine NOT having it!

Whether it’s a system like ours or something similar, it doesn’t take long to see that an at-home purification system is the most convenient, safe, affordable, and environmentally friendly option.


Ocean Plastic Pollution

Buying bottled water is a serious environmental issue. We see a disturbing amount of plastic floating past us every day…and we know we’re part of the problem.

Just how much plastic is in our ocean?

In 2012 5Gyres gathered a group of scientists to find out. They determined that there were 269,000 metric tons and 5.25 trillion particles—enough to stretch to the moon and back, twice.

We really love the work and education that is doing.  We love it so much we signed on as 5Gyres Ambassadors!  If you want to learn more about the problems our oceans face and what you can do about it, please check them out.



Sharing this unsedentary lifestyle and what we learn along the way is possible because of viewers like you.  If you like what you see, there are lots of FREE ways you can show your support.  Thank you for being a part of the journey.


Don’t Listen to People On The Internet!

We always say, do your own research.  So don’t just take our word for it (or anyone else’s).  We’re always in a state of learning and new information comes out all the time.  The more we all fact check and share information, the more informed we all are.

Here are some of the resources we use when learning about water:

  • Wikipedia (loosely as it is crowd-sourced)
  • Environmental Working Group (
  • Environmental Protection Agency (
  • Centers for Disease Control and Prevention (

Hello there! I honestly don’t know what to say, so I am going to tell you a bunch of random facts instead. I'm a fish eating vegetarian who hates spiders and loves snakes. I almost never took vacations growing up. I wanted to be Pippi Longstocking (still do). I misspell about every other word I write and still struggle with grammar. I love splurging on a good high tea (which is really hard to find these days). And whatever you do, don’t tell me I can’t do something, because then I'll HAVE to do it!

Comments (57)

  • Matt

    If filters can’t purify water, how do those backpacking portable water filters stop me from getting sick numerous times on camping trips?

  • Lucky the sailor

    So if the water in the storage tanks going funky due to bacteria is the first problem in the chain, why not stick a UV tube in the tank? Atlantic Ultraviolet sells the Tankmaster series of tank storage sanitizers. I’ve seen some models that run on 12v and only draw 12 watts… although twin 100 gallon tanks would likely need something more powerful.

    I’m not advocating this as a solution; just wondering if anybody had considered it as an option?

    • Curious Minion

      For UV sterilization to work you need a high concentration of light/water. That’s why you’ll most often see water channeled through a smallish pipe that contains the UV light – so the light can penetrate all of the water passing through. The 100 gallon tanks are just too big (you’d need waaay too many lights).
      Curious Minion

      • Paul Bartomioli

        So, wouldn’t it make more sense to install the UV set up on the outflow of the tank? IF the UV is only on the kitchen sink, what about head sinks, showers? Or is there a “maintenance interval” to be followed to clean water tanks periodically?

        • Curious Minion

          It would make a lot of sense but I’m guessing there’s a really good reason that they didn’t install it there. My guess would be that there’s no place to tap into power there but that’s just a guess.
          Curious Minion


    Good afternoon. Thank you…Love your blog!

  • Keith Moser

    First let me say how much I enjoy your your videos you guys for allowing me to follow and live a little through you. Now I have one question for you two concerning your catamaran. Are you still happy with your choice do you wish you could have a different model or make. You had three choices in Florida what were were they?

  • Eric


    I have used UV, RO, and Carbon filters as filtering devices. However, they do not purify or disinfect the water.

    For me the two best water purification solutions are a water distiller and water chlorination.

    The water distiller is only for drinking water.

    The water chlorination is to kill everything in the tanks and pipes. This can be done with a micro liquid dosing system which places a few drops of chlorine every time water flows from the outside into the tanks.

    Alternatively, you can estimate how much new water you stored, and take a spoon or cup to pour the correct amount per volume of water.

    The distiller uses about 800 watts per hour for about 3.5-hours per gallon of water. This is enough water for two people per day.

    In addition, when water is of obviously poor quality, we use Microdyn to disinfect vegetables and fruits. Fifteen minutes is usually enough. Use approximately 1/2 teaspoon per quart of water.

    These ideas will kill many but not all bugs. The one thing they actually do is decrease the concentration you could get from them at any one time.

    Water is, as you know, one of the top health problems in developing and tropical areas.

    Stay safe, stay healthy, and stay strong.


    • w3w

      The “800 watts per hour” is a nonsensical value. *Watts* is already a rate of consumption. Differentiating/integrating that by hours makes absolutely no sense.

  • Sam and Sydney

    Feedback from a Patron ;0 just bought the system and added it to our refit path. We have completely rebuilt our water system and other than a RO system this was the last component.

    Sailing Vessel EOTI

  • Bernard

    Once a year, I add a cup of baking soda in each of my tanks (75 gallons X4). I also add half of a table spoon of chlorine in the tanks, then run the boat for a day or two, empty the tanks and fill them again. If it doesn’t cure everything, it helps the tanks to have a good start in the early season.

    Second point : to bring back minerals in purified water, you just have to add 3 drops of sea water for each one gallon jug, and, amazingly, it does the job. Thanks for your great videos !

  • Michael

    A couple huge mistakes. #1. One does not want anything in the drinking water. No minerals or other contaminates or it is not just H2O; it is water with impurities. The more things in the water, the less can be washed out of the bodies cells. If the coffee is missing something, add it to the coffee, not the water. #2. The only 100% way to get clean water is distillation. Period.

      • Luke

        I disagree.There is a lot of disinformation out there on the subject for various reasons.Minerals in water are from rocks.Do you really think the body can use minerals in this form? Minerals from plant baised foods.

  • Haze

    I love your presentation style it is both competent, casual and authentic. Kudos.

    My question: What about non-drinking water? Especially in warm climates where your tanks are at the ideal temp for Legionella… you get Legionnaires by inhaling microscopic droplets in the shower. Or possibly as residue on plates etc.

    I love the Acuva solution for drinking water. It sounds like a miracle- never/rarely have to clean tanks, never have to chemically treat the water, never worry about where you got the water…

    but.. that still seems pretty unsafe if you’re using non-acuva water for showering/washing up, where droplets / residue can easily end up being consumed. It seems it would be ideal to use the acuva water for everything, but as far as I understand it ONLY leads to the acuva tap?

    Is there a solution to this?

      • Todd Weiden

        Do you all have a video of how to installed the WHOLE HOUSE WATER FILTER mentioned above?

        • Curious Minion

          I don’t believe there is one for that Todd. Maybe check the manufacturer website? Or there’s sure to be a few on YouTube by various people.
          Good luck with it!
          Curious Minion

    • Ron

      Random thoughts – Legionella is naturally occuring in most ground water, you can test the same water source multiple times and get multiple results. Know that you have (and will) consumed Legionella in your lifetime. The amount of hysterics associated with little knowledge is mindblowing……. If you are under 50, fairly healthy non smoker you have little to worry about. If you are in one of the groups (HIV +, smoker, 50+, overweight) with a compromised immune system use chlorine with enough CT(contact time) or ultraviolet light sterilization . I don’t think you want to tackle ozonation, or copper-silver ionization or steam heating
      Pontiac fever is also caused by Legionella. Residue won’t getcha there, neither will consuming but fine spray mists will so stay away from supermarket misters in the veggie isle. It is a severe form of pneumonia treatable with antibiotics, but exposure to Legionella doesn’t mean you will become ill. There are 329,034,082 people in the US and 18k a year get ‎Legionellosis. Worry about those spearfishing skills so you can eat sushi, raw fish CAN harbor parasites, bacteria, and viruses …..oh no here we go again!

  • Deborah Kerr

    Even if I didn’t care about the water filter information, you all are just entertaining – including the cat kids!!!
    Thank you for the smiles!! 🙂

  • Norman Frenk

    I found this interesting article about silver as an anti-bacterial agent for water. Perhaps you can store your silver bullion in your fresh water tanks.

  • Marsha

    You mentioned carbon filters, does the RO have a filter? Do these need to be replaced, how often & are they recyclable?

  • Stev Schwendi

    Thanks for being awesome!

  • Patreon - John

    Looking at this option for my new Catarmaran, I like the idea of putting minerals back into the water. What was the brand name you use please?

    • Curious Minion

      There are links to the filters in the blog post and under the Acuva system post in the Gear Store.
      Curious Minion

  • mary

    I like the special effects, kind of fun!

    Grandpa uses similar water filtration for the water in his home. 🙂 I did not know that you re-mineralized the water. Good to know!

  • Heather Stewart

    Dear Curious Minion…as much as Mary has relegated you in your “favorite” status … it makes me smile to see you jumping in when J & N are “further off the grid”. 🙂 Thanks for continuing in your “family” contributions…and wishing you the continued best in your evolving journeys. <3 That is all for now. 😉

    • mary vancompernolle

      She may regain the favorite status jumping back in and helping out. Thanks, Kate!!

    • Curious Minion

      Thanks Heather! Nikki & Jason aren’t just my bosses – they’re good friends and a big part of my Nomad Family. Thanks for all the good wishes.

  • Alan Solomon Solomon

    Great information Nikki and Jason. This informative video as usual is a great source of information to access when I am considering my next move concerning drinking water.
    I have to say I am not completely plastic free yet but, very motivated to stop single-use plastic today and I know that starts with me.
    I like the Acuva unit and your decision to remineralize your water. I think that is important.
    Super job. Hi Kitties.

  • Roger B

    You’ve confirmed our selection for water purification. Thank you for this video.

  • Joanie

    I ama water nut and I live where my well water is. I spoke to my plumber in the fall and told him I wanted to change the system I have this spring. Now I am going to look into Acuva, or get his opinions in general then get specific about it. Right now I have a 3 step system. Whole house. Sink filter from the health food store. Then another pitcher system that I think adds an h202 molecule in its filter cap. Water is really important to health whether you are mobile, off or on grid, and have your own well. We don’t know what the weathermodifcation company is spraying. Especially now that there are so many operations buzzing around. Love your ‘training vid!

  • Bob Sprengel

    What about washing/rinsing dishes, cookware etc.? Are you using unpurified water with that other faucet or shower outlet ? Won’t the rinse water leave residue that may be harmful? What about showering? Water can be ingested if not purified.

  • Chris

    What is your back up for water purification during passge/ long periods at sea ?

  • Theresa

    Hi Guys! I absolutely love you both and Appreciate all the Lovely, informative and fun to watch videos y’all create! You guys are truly killing it!!
    Now for my question, what do you guys wash your dishes with? Just curious if you use the same high-quality UV cleaned drinking water to wash dishes with?

    Thanks and love y’all!!!


    I thought that the R.O. Water maker does take out all bacteria and viruses? We have one in our home that purifies our well water and the Literature that came with the product specifically said it did. So is it your storage tank that is the problem and you R.O. Is just used as a deslinator?

    • Curious Minion

      Yes that’s essentially it. Because of the size & shape there’s no good way to clean the storage tanks. From time to time they also add water from municipal sources and that should usually be treated with suspicion.
      Curious Minion

  • Debbie

    Does your Acuva support your icemaker?

    • Curious Minion

      Nikki and Jason are still struggling with connectivity at the moment but hopefully they’ll see this soon. I *think* they just use ice trays in the freezer, so yes, those would be filled from the filtered drinking water tap.
      Curious Minion

  • Kevin Petrey

    To piggyback off Donald Wheat’s question. Are you happy with that size boat for 2 people? Have you done a comparison between RV living and living on the boat? Thanks!

    • Curious Minion

      Nikki and Jason are still struggling with connectivity at the moment so I’ll jump in. See my answer to Donald’s question regarding some of their criteria for choosing Curiosity. They have mentioned before that they wouldn’t want a bigger boat: Curiosity is enough to maintain and keep clean and is still easy for the 2 of them to sail. But she also gives them a fair amount of room to entertain friends and family, which they do fairly often. So I think Curiosity hits the sweet spot size-wise. They’ve also said that they prefer a cat layout to a monohull.

      No, they haven’t done a full comparison of RV vs. sail life, but past answers that stick with me are: 1) sailing life is harder because boat maintenance is just never-ending, 2) they still love RVing and will do more of it, but right now they are happy sailors, and 3) the thing they love best about each is the camaraderie and community of amazing like-minded people. Hope that helps.
      Curious Minion

  • Katherine Crosbie

    I have heard that you shouldn’t filter your water when you fill your tank because you remove the trace amounts of chlorine in it from the public water source. As a result, you are more likely to get bacteria or mold growing in your tank. That said, do you use anything to keep the water in your tank relatively clean/odor free before you filter it for drinking?

    • Peter H Coffin

      Not an issue. Chlorine doesn’t stay in the water in an unsealed system. A municipal water source is a sealed system right up to the tap. Once you put it in a jug, it’s not sealed anymore, and the chlorine starts coming OUT of the water. That’s why you can smell it, right? It climbs out of the water, floats in the air, to your nose. Not all of it comes out, but the more exposure to air it gets, even in the tank, the less chlorine is in the water and the less effective a sterilizer it is.

      Which gets us to another complication with chlorine: the most common and easy source for doing your OWN chlorination is chlorine bleach. The problem comes from that once that bottle stops being a sealed system (that is, it’s opened and some of the bleach starts getting replaced by air, there’s a time limit on the bottle now too, as chlorine starts coming out of the bleach. (That little screwtop isn’t a great barrier to prevent it from getting out of the bottle either. Not compared to the glued seal that was there before.) So after a couple of months, the open bottle of 6 or 8% chlorine bleach isn’t 6 or 8% anymore, it’s like 2 to 4%. Which means the amount of product you need to add to a tank when filling to treat it is going to change. Or the amount of time it will take to work is going to change. Or both. Which also means you’re going to need to replace that bottle of bleach on the regular. Bleach is inexpensive, but you’ve probably not used more than a couple of ounces out of the bottle for water treatment, so the inclination is to keep it longer, even though it’s getting more useless by the week. Which means you need to expect to buy at least a half-dozen bottles of bleach per year, throw out or use up a bottle every eight weeks, whether you “need to” or not. Again, not really EXPENSIVE, but counter to most people’s instinct for frugality.

  • Scott Taylor

    You may want to investigate ceramic filters. The system I use on the road consists of one of those carbon/spun wrap sediment filters, then I run water thru a Rio 2000 high capacity ceramic filter. This type of filter WILL eliminate many organisms such as giardia, E. coli, and cryptosporidium. UV systems don’t actually kill organisms – they “sterilize” them, meaning they don’t reproduce after you ingest them, but they are still there! Interesting side note – The National Park Service notes that SteriPens are ineffective against certain organisms in and around Isle Royale National Park, and as such recommend boiling water. So…where else and what other organisms “immune” to UV?

  • Michael

    Good video. Stay viligant. Maybe we will see y’all in a year are so !!

  • Jeffery drew

    Hi guys enjoy your videos very much like saying you guys out there one quick question you guys heard of hydraulic charging system for boats or chargers your battery why you’re sailing if not you might wanna check that out those days when you don’t have solar you got a charger batteries you can have the water charges this a food for thought up to see is good kind to you your travels are good and the winds at your back have a great day

  • RVgeeks

    We have loved and trusted our Acuva water purifier for over a year as well. Glad you’re not getting sick out there on scurvy water!

    • mary

      I was going to ask if I need this for my RV and didn’t want bother the curious minion. Thanks, I will catch up with you for more details.

      • Curious Minion

        You are never a bother Mary, but if you play your cards right you could probably get Peter & John to install the system for you! ;o)

  • Donald Wheat

    Question, are you still satisfied the Leopard 43 was the right choice or is there another more satisfactory choice to consider? Would a Leopard 43 PC ever be worth considering? All this for the cruising and living aboard you have enjoyed. We are considering moving onto the water after years in our 34′ HMC Hawkins Motorhome.

    • Curious Minion

      Nikki and Jason are still struggling with connectivity at the moment but have answered this before so I’ll paraphrase. In short, it’s like choosing a motorhome: there’s no right answer because everyone’s needs are different. They chose Curiosity in large part because it was one of the brands they had narrowed their search to (for quality and reliability issues), she was an owner’s version and not a charter version, and she was within their price range because they wanted to own outright. Would they like to have a faster boat? Sure, but they weren’t in their price range. Would they have liked a boat that didn’t require all the service visits and outfitting that Curiosity required in their first 2 years of ownership? Sure, but again, not in their price range. As for a PC, that would be a deal-breaker for the Wynns because they wanted the option of traveling primarily via wind-power because they are trying to reduce their fossil-use footprint as much as possible.

      But what’s right for the Wynns may not be right for you. They have recommended to other boat shoppers to try out the boat you’re thinking of if possible. If not, try to find a forum geared toward (in this case) power cat owners and try to pick their brains about what they like and don’t like. I think it’s very much like the process of shopping for an RV – just harder to take them for a test drive. :o) Hope this helps.
      Curious Minion

      • Donald Wheat

        Thanks, I am also considering the Island Packet Cat 35 and a Fisher CatFisher 32. My thoughts tend more toward redundancy, storage and tankage and ease of one-handedness.


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