Anyone used an under sink reverse osmosis unit to purify water FROM FRESHWATER tank

[Kenomac]

OP,

Just have Tellie or Rich install a watermaker, then you'll make as much fresh water as you desire which will also be as good if not better than your city water. Ours tested 180 ppm earlier today, with source water from the inner-most marina inside Brindisi harbor, Italy. We run ours every day for a short time instead of flushing.

[Bill Seal]

If all you want is good drinking water, something like a 2 or 3 stage under-sink filter with it's own faucet might work, and you won't be wasting filter cartridges making good tasting dish washing water.

[Kenomac]

Originally Posted by fryewe

Under sink RO salesman came to my house (years ago). Wanted to sell me a system for a coupla grand.

He pulled out his test kit and tested my water for TDS and voila!, the TDS was high (California city water - go figure).

He had a filtration system with him. I asked him to hook it up and show me how effective it was...by doing a TDS test on the filtered water after hook up and flushing.

"That'll take too long!"
"No one has ever asked my to do that!"

I refused to talk to him unless he hooked it up.

We hooked it up, flushed, and tested for TDS.

TDS was unchanged by his system.

No sale was made that day.

Sounds like a Kirby vaccum salesman trying to sell you on how much more his vaccum will suck than your current vaccum.

They both suck.

[MarkJ]

Yes, i have seen the units in Egypt where they use them to purify river water for the house etc.
In my 8 years flipping round the world i have never had a bad batch of water xcept for ver chlorinated stuff a few months ago. I did buy bottled water then.

Economically, it would depend on the length of the cruise. If u are doing 8 years and you are a pedantic person it may work out better to get the RO... They were very, very cheap, maybe $1,000 USD?

BUT over a long cruise you do need to look at your health and 8 years on bottled and/or RO water you will probably be anemic. Whats more important to you? Your long term helth and longevity, or the trendy thought of pure water you then plunk coffee into?

I go for tap water everywhere for health, economy, ecology, and humility


Mark

[BHI_Guy]

In St John USVI, where all houses catch rainwater off the roof as their water source, most people have RO filters to purify the water when it is drawn from the cistern under the house, but for a freshwater tank on a boat, this seems excessive. Also, those types have two filtration elements after the pre-filter, followed by a UV bacteria / virus killer. Might be kind of bulky for a boat. A simpler, cheaper way would be to buy a backpacking filter if you really want to purify the water. First Need filters are heavy duty, easy to pump, and will get everything, bacteria and virus, out of the water. Another simpler, cheaper possibility is the Sawyer Squeeze filter which has no moving parts, or one of the gravity fed filters. Another possibility is a Steripen, which is a UV sterilizer.

[jcord]

Hi
We have a Tyent water system for reverse osmosis. We have used one for many years and I would not live anywhere without it. We have our 42 ft Sailboat as well. When we move aboard permanently as we are planning on doing next year, it is the first thing that will go with us. We have the under the counter unit as before we had the on the counter one. I have found the people there at the company to be super helpful over the years. This is our second unit now and have had these for 15 plus years. You might call them and just ask a few questions as well. They have always been helpful. I truly love the water from this so it is a priority for us.

[Dave22q]

I want to be kind but... Unless you make a practice of filling your tanks with swamp or sewer water this idea is absurd. Talk about solutions to non problems. BTW whatever gave you the idea that bottled water is superior to tap water (at least here in the US excepting Flint Mi)?

[reed1v]

We ran a RO system for 10 years, mostly on a continuous basis in all types of horrible waters. Worked well. Don't see a problem with doing the same with your water tank. However why not just buy a ton of bottled water for drinking and be done with it?
BTW, a full water tank is less likely to get fouled than one that is part empty. Less air and its contaminants to foul the tanks.
BTW2. A RO system should be run on a continuous basis; otherwise you need to pickle the screens after the system has been down for a while. For a while can be from a day to several days, depending on the design. Filters that dry out need to be clean before that happens or you risk damaging them. Otherwise just use a camper's RO system when you want to filter your water. Still need to clean the filters, but a smaller task.

[lfalco]

I'm with Kenomac. Fresh water does develop a funky taste from sitting in my plastic 20 gallon water tank. I clean the tank often and still I use a Brita and change the filter at least 3 times during the hot summer months. Haven't been ill or died yet! Just gives additional peace of mind.

[reed1v]

Originally Posted by Dave22q

I want to be kind but... Unless you make a practice of filling your tanks with swamp or sewer water this idea is absurd. Talk about solutions to non problems. BTW whatever gave you the idea that bottled water is superior to tap water (at least here in the US excepting Flint Mi)?

Yup, most bottled water is from tap water. Poland Springs dried up decades ago up here in Maine. But its name is still being used by Nestle. Now about Mrs. Trump's dress....

[Brooderman]

I've used a system as you've described in my homes for the past 30 years. I wouldn't do without one on my boat either. It's just an insurance policy that the water you drink is as pure as possible. The "waste" water shouldn't go back into your water tank. Get a second tank (even a jerry can will do) to catch the waste water as it is still good enough for washing, rinsing, and other non drinking purposes. I think the ratio is about 10 to 1. So ten gallons "wasted" to get one gallon super pure r/o water that's also been carbon filtered as most of these systems have a carbon filter as well.

We promote redundancy and spare parts everywhere else on the boat, I'm certainly not going to trust the water I drink ( Let's be clear - this is for drinking water only - not fresh water in general) to anything less than my best effort to be sure it's pure. And these systems are cheap now - $300 or less at Amazon or the big box stores. And the filters don't need to be changed nearly as often as they recommend. Buy a Total Dissolved Solids tester (cheap on Amazon) to test your drinking water - when the results start to creep up then change your filters.

Nay to the Nay sayers. Not to do this is pennywise and pound foolish. I wouldn't trust anyone's marina water tap or water caught off a tarp during a rainstorm. Even the rain is polluted these days.

Sure you have a water maker - great! Then you store the water in a tank that's growing who knows what.

Redundancy! - (This message approved by the department of redundancy dept)

[Cheechako]

Only problem I see is the more you reject back into the tank the worse the water in the tank becomes. Not sure the end result of that.

[barnakiel]

Your idea is not silly and I think you should make a deeper research maybe then prototype some and see what happens.

Never listen to people who never did this but will tell others this or that can't be done. Like Hillary would never have climbed THE mountain.

I have seen a small RO brackish water unit employed on a big maxi size yacht. One of the big players. It was in the bay under the sink. Unit made in Catalunya sized for off the grid weekend households (finkas=huts) with brackish wells. I cannot tell you how it was wired but the tap of it exited just next to the fresh water tap in the galley. Clearly this water was then used in the kitchen. (?)

Do you want me to look up that installation to see how this RO unit is wired into the (many) tanks? I have seen such units in local shops.

Another clue: In Sweden they have showers that cycle shower water in real time. Not sure what process they use, perhaps low pressure RO or light or a combo.

Cheers,
barnakiel

[luckysailor]

hmm, think your idea is not practicable since you will waste a lot of water or you will increase the salt content of your tank. Further chlorine, which might be in the tank-water, will destroy your membrane.
What I did on my boat for fresh water: I installed a 3-way valve at the outlet of my RO (from saltwater). One way is connected to the tank, the other goes with a non-valve cock to the sink (never lock the output of the RO, it might destroy the membrane). During start up, I drain to the sink, but I use this way also to fill up bottles with clean water, which had no contact with my tanks. Mostly I fill up first the tank(s), at the end I fill some bottles.

If you worry about quality of your water tanks, just install a ceramic filter plus active carbon filter. This will do it safe, easy and without needs of energy.

[patfarrell1949]

For what it's worth...we own a home in Yucatan, Mexico and have city supplied water to the house. For drinking water we run the city water through an under counter RO system (uses city water pressure and found easily on Ebay) to remove what we've been told may be sometimes harmful organisms (read Montezuma's revenge stuff!). System is set up basically same as our boat's RO system with filtering first and a membrane next. I'm guessing the reject rate is something like 50% or so. TDS of the drinking water drops from 200+ppm to 30+ppm. Of course that also means the reject water TDS rise to something like 300+ppm..but not measured.
System has been in continuous operation for a couple of years with zero maintenance (unlike on the boat!) and no Montezuma's revenge...though we may have been fine w/o the system as well.
I could see using the under counter system on the boat when hooked up to dock water of questionable quality and I could send the reject water overboard. But using salt water as our input source, it wouldn't make much sense to refilter when I already am producing water at 30+ ppm.