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I'm ready to install my flake ice machine but I need a multi-stage water filtration system with UV to feed it. The package will also feed both faucets and shower with the exception of the cockpit fresh water washdown, it seems a 8-10gpm system is the correct capacity. It sure would be nice to drink the water for a change. Does anyone have a source? Thanks, Mike
Mike,
I just bought a new U-line icemaker today to replace the dead one in my wetbar and was thinking of a filter for it as well. A few months ago, either Yachting or Power & Motoryacht magazine did an article on the quality of the water in fresh water tanks aboard boats, including several megayachts. Most boats' tanks were fed by watermakers, so the water being put into them is about as pure as it gets. Unfortunately, they did find surprising levels of "undesirables" in all tanks, even the newest tanks and tanks that were supposedly properly maintained. The conclusion was to drink bottled water while aboard to be safe, and use the water in your tanks for everything else. I believe that ice falls in the gray area, as you never drink any large quantity of the water by simply using the ice for cocktails, etc. so that should be fine.
Several months ago I replaced the dying refrigerator with a standard 22 cubic foot GE side-by-side that has a water filter built in so that the ice it makes and the water it dispenses is filtered. Who knows how good that filter actually is but although I do use it for ice in drinks all the time, I still do not drink the water. I fill my tanks with city water via marine hose and I add a cup of bleach in with every 200+ gal fill-up. I do use it to brush my teeth, but I try not to swallow it just in case.
I will be quite interested as well to see what the experts on this forum have to offer on this important subject.
Thanks for the reply, My ice maker is designed to make around 200-250lbs of ice when set up to run overnight, thats around 30 gallons. The idea was to use it as drink ice too as the Bahamian ice gets a little pricey and questionable. I figured a 3 to 4 stage UV super duper filter would do the trick. Mike
Crud in tanks can be surprisingly significant. But don't think your home is any better. Just cut open any water line in your home and you'll be amazed how dirty the water lines are. After thirty years, some become calcified and the water lines flow severely restrcited. Apparently all water carries some sediment and over time it builds up.
I just changed the heating element in my hot water tank a few days ago...I stuck my finger in the 12 gallon tank bottom where the heating element was previously mounted...rusty crud came up to my first knuckle....this is a six year old stainless steel tank. The tank itself was shiny as new...I assume the rust muck came from prior heating elements...I replace them every other year and they are always corroded..I had never peered inside the tank before with a flashlight..it was scary..
In this case, I got a hose aboard with a spray nozzle and "pressure washed" the tank putting the crud into solution..after three rinses the water drain was finally clear....now the rust muck was in the bilge so I had to rinse that as well and then pump it...but all is clear for the time being..
There is no system that can match a well placed drain to permit periodic rinsing of fresh water (and fuel) tanks...Alas, that is all too rare..
I have cannister water filters at the wet bar and the galley sink. I've forgotten the brand but they are about the size of a large auto oil filter with a replaceble element. I also put a cup of clorox in every time I fill the FW tanks. I run the tank out of water at least weekly so it's turned over often which, I think, is a critical issue.
Frankly, I used to drink the tank water all the time but the Admiral is adamant that we not drink it (She also won't drink "bathroom" water at the house - go figure). So we carry bottled water for general water-drinking. However, she's OK with ice cubes or teeth-brushing. When I'm on the boat myself, I make coffee with the tank water but she's pretty much trained me to drink bottled now.
In any case, I have found Mount Gay rum to be totally safe at all times. In fact, I'm drinking it even as I type with absolutely no ill effects!
The best (cheapest) place to get "whole house" water filters is....Homeless Depot. I have rough, fine, and uv filters in line just after my pump manifold, and they work great, no taste. I also run my watermaker all the time to load the generators, so the feed water is a good as it gets. But even if I fill up with SoCal tapwater (aka mineral concentrate) I can't taste it.
Seagull IV filter is the way to go , see this link http://www.drink-water.com/point.htm..............Pat
Just a point to make: ice made from contaminated water is NOT safe and plenty of folks have gotten sick off of it. I don't think that tank water in a boat ought to be consumed (ingested) unless it was filtered and UV treated and, as Mike says, turned over frequently. The basic problem is that unless you live on your boat and use the water system all the time, stuff sits and grows in there.
The basic things that can make you ill from drinking tank water are as follows:
1) stuff that's alive- this is bacteria, viruses, protozoa, and fungi. Usually a combination of filters and UV treatment will reduce these levels to safe, but not always.
2) stuff that's poisonous: fuel, solvents, cleaning solutions, etc. Usually the taste puts you off these, but not always.
Having lived aboard for many years, I used tank water for showering and dishwashing only, and kept bottled water on the boat. I do not recommend tank water for brushing your teeth, or drinking. It may be safe to cook using tank water, but you don't really know. I think if you have a good multistage filtering system plus UV treatment, you can be somewhat reassured. Frankly I would still carry bottled water for drinking.
Having treated countless cases of "turista" over the years, and also experienced it myself, I carry a cooler of ice and bottled water for drinking. Not all the illnesses that people acquire from bad water are brief- it is possible to get Hepatitis A, as well as various fungal infections that can be quite serious, from bad water. Better to avoid it.
Oh, and as Mike said, rum, while having its' own risks, is safe with regard to the issues at hand. Ice, however, is not. Mixed with lime juice and bottled water, however, rum is safe and traditional.
Mike, a cup of bleach is way too much for 200gals. 3-4 ounces would be the correct amount based on the research that I have done. I can’t reference that at this time but will if you require.Quote:
Originally Posted by ThirdHatt
I'd be interested in what the right amount is.....at my last fillup (250 gallons), I put ALOT more than a cup of bleach in....
Ouch, don’t shower in that. :eek: I think a cup of bleach for that amount of water is used as a shock to the tank. I’ll get the info, but it will be Mon before I can get back to ya’.
For now, I’d drain the tank (including the hot water heater) and keep flushing it until the bleach odor is gone. You might be surprised at the crap that will come out of there.
To render water potable with bleach, the correct ratio is 1/2 teasoon (.33 oz.) of bleach for every 5 gallons of water.
So I guess the correct amount with our FW 287 gal tank would be about 5 oz. I have to say that the amount I put for routine use doesn't produce a noticeable chlorine odor.
At the beginning of the season, I put a GALLON :eek: of clorox in the tank, then fill it completely with water, run the water through all the fixtures for several minutes, shut off the fixtures and leave it overnight, making sure the icemakers are empty so they will be making ice all night. Next day I run all of the water out of the tank through all the fixtures, fill the tank again (no clorox) and run the water out through all the fixtures. Then I add a "cup" of clorox and fill the tank again. After this, I empty the icemakers again and let them make ice for a day before using any of the ice.
I have to admit I don't measure the "cup" of clorox I put in - a couple of "dollops," I estimate it at a cup but it is probably somewhat less than that. Then I fill the tank and consider it done. From that point on, I add the "couple of dollops each time I fill the tank.
There is never any odd odor or color in the tank water from the taps.
Again, we now use bottled water for most things per the Admiral, but I don't know what could possibly be alive in the tanks after that treatment!
Upon revisiting my old research I have found the following:
According to Clorox: Bleach can be used to clean or “shock” tanks before using them to store water. Fill the tank with water and add 1 cup of bleach for each 50 gallons of water. Let sit for 10 mins and then drain it. Rinse the tank with water until the taste of bleach is gone.
For regular maint: According to my research of public water systems (reference I can’t find at this time) you want at least 0.2 ppm to no more than .6ppm free available chlorine in the system. And you get that from the city water supply anyway. Therefore, no need to add any to the system.
Shocking the tank once a year may be a good idea. Adding bleach every time you fill up is unnecessary.
I know guys who take on 400 gals on their way to the Bahamas and drink off that for months without ever adding bleach and their water stays ok.
I still would not drink from the tank untill a proper filtration system is in place to remove anything the tank may add to the mix.
For those who are interested I put together the water filter system for my 36. It consists of a 10" housing for a 5 micron pre-filter ($39.99), a 20" housing for a .5 micron carbon filter ($55.99), and a 5gpm 110v UV sterilizer ($239.99). The filters run $7.49 for the 5 micron and $25.99 for the .5 micron carbon. Complete system cost w/ 2 of each replacement filters and shipping ran $455.00. A 12v UV was available but the folks said to leave it on 24/7, I was afraid of it draining the battery in the event of shore power loss so I went with 110v. I'll set it up be on anytime there is 110v available (a small inverter could be used), lamp life is forecast at 8000hrs ($75 per replacement bulb).
I system may be a bit overkill but it will protect the entire boat including the shower and ice machine. We cruise the Bahamas a LOT and the water purchased at out islands can be questionable, plus I've paid $1 per bottled water (case price :eek: ) now we can drink from the faucet.
I'm not sure forum rules allow posting of the product sources (internet) so if anyone wants them PM me. Mike
Re: icemakers....There was a highschool student in the news recently that did a science fair project of visiting 30 fast food restaurants. She took a sample of water from the ice machine, or ordered a cup of ice. Then she went to the restroom and took a sample of water from the toilet of each restaurant. She then analyzed the contents for critters.........you guessed it!......the toilet water had less bad stuff in it than the ice machines!!! :eek:
It turns out that they're very hard to keep clean inside and that there are plenty of bacteria that do just fine at 25 to 30 degrees.
My icemaker works OK, but we never use it, unless to use it as a secondary referigerator on a long haul with the genny running.
Doug Shuman
I pulled out my icemaker and replaced it with a bar-size refrigerator. Then we replaced the galley fridge with a side-by-side with ice in the door. The galley fridge water runs through the filter under the sink and then through another charcoal filter in the fridge itself.
Mike,
Do you plan on using the water when you don't have 110v available? Will this contaminate the water in the lines if it doesn't run thru the UV? I also would be concerned about drawing down the batteries with the 12v uv light. I guess that you could replace your FW pump with a 110v pump so that only treated water is passed thru the system.
Mark
I use peroxide to treat my tank. It's so much easier. Just put it in when you leave the boat, when you return the work has been done. Any left in the water evaporates. No taste. You guys have never lived in the country. We have used holding tanks and cisterns for our water for years.
BILL
FWIW, I have lived aboard with my wife, and occasionally daughter, for over 7 years, and the previous owner lived aboard with 2 daughters for 2 years. We both used tank water for everything. I did add a home depot filter that has not only the sediment filter, but an internal charcoal filter. I set it up to only filter the water on the cold water side of the galley (the filter doesn't need replaced too often that way) and our ice as well as drinking water comes from that faucet ONLY. We also add just under a cup of bleach (clorox brand, as I read somewhere it is the purest) to 250 gallons of tank water. No taste and no odor.
So far no one has been sick by unknown causes that might be related to drinking tank water. I know not everyone lives aboard, however, we now live in SW Florida and it DOES get Hot down here. Our tank only lasts about 2 weeks, but again, we have had no problems drinking the tap water. Hope this information helps. If I only spent weekends on the boat, I would probably do the same, except I would only add enough water to the tank (and the appropriate amount of Clorox) to last two or three weeks.
Also, I only use tank water till it runs completely out. It will invariably run out when my wife is in the shower, so dock water is always hooked up to the boat, but with a shutoff valve at the inlet to the boat. When the water runs out, a flip of the quarter turn valve allows completion of the shower and whatever else needs done, until the tank can be refilled.
I almost forgot. As well as bleach, we add 2 teaspoons of a water conditioner from Starbrite. I don't recall what it is called (PM me if you want to know and I will look it up and report back) and it does a superior job of lproviding VERY fresh tasting water!!! Again, FWIW
Norm Mayer
Aboard Runaround Sue (1970 44' Hatt Tricabin)
in N Ft Myers, FL
I’ve been giving this a lot of thought lately and I’ve come to the following conclusions:
I can no longer see the need to add bleach/peroxide when filling up, as the city supply should already be germ free. They treat the water with chlorine before they send it to you and in the proper proportions. It’s already in there. If you add to it you could end up hurting yourself.
When storing water in a tank there is the potential for crap to grow. UV lights are good for dealing with critters if they start growing and regularly shocking the fresh water system (water tank, accumulator, hot water tank, plumbing, fittings) will kill anything in there no matter where in the system it may be living. And you’ve got to filter this dead crap out or you’ll end up drinking or brushing your teeth with them. :eek:
Perhaps our focus should be on keeping our fresh water system as clean as possible instead of treating water that has already been treated. :)
For peace of mind, whether you drink the water or not, is to filter what comes out of the system and have a water testing program in place. Without a testing program you just can’t trust that the water is clean after it comes into contact with the boat, and it is the only way to know for sure whether your water systems are clean and in good shape.
I agree. Shock it, so you know that it's clean, and then use it. And by using it, I mean don't use a dockside pressure hook-up. If you don't continually replace the water in the tank, it will not continue to be safe to consume. But, if you start with a clean tank (after shocking it) and you continue to use already treated water (from the municipal supply), then you should be good for quite a while. The real problems come from the lack of use. This is why all of the liveaboards don't seem to have the problems that the weekenders have.
Peroxide is a perfectly acceptable disinfectant for water, as it oxidizes, as does chlorine. There are couple things with peroxide that make it different from chlorine as a disinfectant. Peroxide degrades even more rapidly than chlorine and potency may be an issue if it is to be stored.
The other thing that makes peroxide more difficult to use is that testing for peroxide residual levels is difficult compared to testing for chlorine residuals. Residuals need to be measured to ensure disinfection is complete. This is dependent on the bacterial loading (how many "bug" part per million parts of water) of your water source. There are various methods of testing for bacteriological levels, but measuring residual levels is much simpler.
"Residual" is that which remains from the original dosage and has not unreacted (potentially to prevent reinfection). Example: if one cup of water has 20 parts per million 'bugs' in it, the disinfectant dosage needs to be at least 20ppm but no more than 25 to prevent ill effects. A dosage of 23ppm (of the active chlorine component) will show a 3ppm free residual while showing a 23ppm total chlorine level (if the background is zero). In other words, the chlorine taste in the water is the "unused" chlorine left in the water after it has killed the "bugs".
Peroxide would potentially have the advantage of breaking down to oxygen and water, but its use is also made more difficult by that fact when measuring reacted components. Because it breaks down faster than chlorine, its “staying power” is not as good as chlorine especially in an open container…which our water tanks are due to the fact they are vented.
A quick calculation to use hydrogen peroxide daily is the required dosage in parts per million, times the volume treated in gallons, divided by 120,000 (which is a constant). This calculates the number of pounds needed to give that dosage. Simple enough?
The short of the long is that a teaspoon (0.6 fl.oz.) of hydrogen peroxide (10-25% solution… look for this on the bottle) per one gallon of water in the appropriate ratio to render potable water. This is essentially double what is required for the use of chlorine bleach.
For a live aboard, who is using a lot of water and continually cycling water through the tank, hydrogen peroxide may be a good choice as long as you are diligent about adding the hydrogen peroxide. For those of us who are weekend warriors of for those who are taking on “questionable water”, bleach is a safer bet especially when used with a simple household type filter with charcoal to remove the “residual” chlorine before it leaves the tap. The “residual” will slowly oxidize or be diluted as more water is added.
I hope this was helpful.
I always find discussions of poteable water interesting, but also see a lot of mis-information included in them. So, I'll jump in here with my 2 cents worth as a four year liveaboard, a 30+ year weekend warrior and a research chemist who spent 10 years trying to understand the effect of poteable water on plastic plumbing.
The water we drink is way more complicated than the chemical symbol H2O suggests. Because it is the closest thing we have to a universal solvent, pure H2O doesn't exist outside of carefully prepared lab specimens. The water we drink has many chemicals and microbes in it. Most are good for us (minerals) and some of the microbes are not.
Preparing water for distribution to our homes is a science of its own, and unfortunately not always well understood by the smaller water companies in the smaller cities of the US. However, they all need to meet well established criteria for drinking water; toxic chemicals, carcinogens and microbes must be kept to a minimum. Unfortunately, our standards do not include maximum levels for chlorine as they do in Europe. Most of Europe used to set 0.1 ppm chlorine as a maximum where here that is pretty much the minimum you find. So we find residual free chlorine levels vary from 0.05ppm to nearly 10ppm. You don't want to drink the latter. A microbiologist once told me 10ppm chlorine in water will kill a horse. But that level is rare, and you can smell it if you sniff test a glass half full.
I mentioned carcinogens. When source water contains certain organic materials such as the flora and fauna in surface water (lakes & rivers), carcinogens called trihalomethanes (THM's) can form when chlorine is added to disinfect the water. To avoid this, disinfection is accomplished with alternative methods most commonly using 'combined' chlorine in the US. If you have something growing in your water system, you will likely generate some THM's if you add chlorine.
In spite of all this, municipal water is almost invariably safe and has enough residual disinfectant to remain so in modest storage so long as you don't run it through a charcoal filter which absorbs the chlorine residual. Bottled water however has no uniform standard. Studies have shown that bottled water can be risky and is frequently or maybe even usually less 'safe' than municipal water. Consider the stuff you get from the local RO system at the supermarket. Does it get tested for quality? When? By who? How about that bottle that you might refill?
So my point is the city water you bring on the boat is likely to be better for you than the bottled water providing you maintain your water system correctly. This includes the delivery hose. We have been drinking the tank water on our boats since at least 1979 and have never had a problem. I can't remember having shocked the system more than a few times in those years only to find out I didn't need to.
What we do is simple starting with a suitable, clean hose.. First, never take on water from a marina that uses a well, unless there is no alternative. Always look for city water. If you must take on well water, then and only then would I consider adding some chlorine, say 0.1ppm. Otherwise, put clean water in a clean system and use it for everything. On Chateau de Mer we carry 180 gallons and that can carry us two weeks if we are cruising and being frugal, less if we are at a dock and enjoying a water source.
The alternative of using dockside pressure water has several downsides. The water in your tank will get stagnant and you won't want to drink it if you go off for a cruise, the delivery hose that sits in the sun all day will produce green water that will get into your system, and if you are as forgetful as I can be, you might go off and forget to turn off the water.
What about filters? Well, if you are using tank water regularly, you probably don't need one. There is not a lot of sediment that gets into city water. The 'taste and odor' filters that have some charcoal in them can be beneficial, and I use them in certain circumstances, BUT they also have a downside. The charcoal that is supposed to remove odors also removes the residual chlorine that you want for disinfectant. When this happens, the very high surface area of the charcoal that does the absorbing also provides an excellent medium for growing bacteria! That is the slime and foul odor you get when you pull one out. And also have a look at the cannister. It will likely be dark or black on the inside. If you must have a charcoal filter and want to minimize the smell from growing bacteria, you can try the 'silverated' filters. These have a fine coating of silver on the charcoal which which acts a biocide. They do retard the growth of bacterial slime a bit, but are not worth the added cost IMHO.
Here in south Florida where the water is high in sulfur, I find the smell generated by the filter builds up too fast; so I don't use it here. When north, we leave it in because it is plumbed already.
Now on to adding chlorine for shocking or maintenance. The city of Miami shocks its water system each year just before the snow birds arrive and start to increase the water usage. The water district told me they use about 10ppm chlorine to do this and that is enough to drive out all the bacterial crud that forms over the summer. And 10ppm ought to be the maximum you use for shocking your system if it really needs it (first make sure the filter is not the cause of the unpleasant taste and odor). But keep it to a minimum. Remember there are a lot of organic components in a boat water system that will be degraded by chlorine, even miniscule amounts. It's progressive.
For maintenance, once you have a clean system that you are using regularly, you do not need to add extra chlorine. Most all of us can trust our municipal supply. If for some reason you want to add chlorine, keep it to 0.1ppm.
My $.02.
Bob
PS, when we used to have to winterize, I found the best approach was to drain all the water out, use a wet vac to suck as much of the water as I could remove, and just leave the taps open. In the spring, I'd purge the first tankful and begin to use the water. No residual taste from antifreeze. Now if you were using vodka....
Quote:
Originally Posted by DeeRow
Here in S FL it's a rare day I don't have 110v available so I'm not really concerned. What I was worried about was running a 12v UV lamp and loss of shorepower while away for a week. A 12v UV system is safer (water quality wise) but not worth the risk IMHO.
I've started the installation and in the process decided not to install the 5 micron pre-filter. I'll use the .5 micron carbon and the UV for this summer and see if the filter life is acceptable.
Bobk, Interesting reply on clorine and filters, please chime in on my situation. My home dockside water is well water, excellent water but non-clorinated. In the Bahamas almost every out island is RO and non-clorinated so each fill-up would pretty much require a shock to be safe. In the past I would add a "glug" of bleach on each re-fill, now I will measure but shocking every time doesn't make sense. As for the carbon filter I understand it removes the clorine I added but it also reduces cysts and metals, etc. basically makes the water "clear" so the UV can do its job. Plus my 500 lb per day ice machine requires a carbon filter. Am I screwing up somewhere? Mike
If your water is free of microbes as it goes into the tank, you should not need more than 'maintenance' levels of chlorine. Check the pH. If above 8, you might maintain 0.5 ppm free chlorine. If down near 7, 0.1 ppm is adequate. The reason for the difference is complicated to explain in a short post, but the oxidizing power of chlorine is very pH dependant. You need less at lower pH.Quote:
Originally Posted by Mike36c
The carbon filter (common taste and odor filter as from Home Depot) will absorb soluble organic matter but does little to remove metals and I don't think it does much for cysts unless they are of the size to be trapped by the filter. I suspect they are small enough to go through the typical filter. You need a water softener to take out metals such as copper, iron etc.
Bob