Drinking Water from watertanks

[a64pilot]

Originally Posted by CarinaPDX

I definitely don't get paying a small fortune for Seagull filters; I'm not questioning their abilities - just the price and availability. Standard 10" filter bodies are readily available pretty much everywhere in the world, and there are many suppliers of filter elements, at a very reasonable price. Personally I have a sediment filter rigged to the filler hose to remove anything coming in, but not the chlorine in the municipal water. Then at the taps I use combined sediment/carbon filters to remove the chlorine and any tank taste before using. When changing the filters it is important to clean the short section between the filter and faucet as the lack of chlorine can allow bacterial slime to build up.

Edit: When choosing filter elements do pay attention to the required pressure: particularly the carbon block filters need decent pressure to drive water through them at a good rate.

Greg

For us it was already in the boat, but to be honest I believe the only real selling point of the Seagull is it’s test scores, if you look them up, and the fact that it has colloidal sliver that kills bacteria.
A filter of course filters stuff, and the stuff is trapped in the filter, if some of that stuff is food for bacteria, then you will likely have quite a lot of bacteria growing on your filter, whether it’s carbon or not.

Copper does indeed have antibacterial properties, and I feel sure if your tanks were copper then it would indeed really reduce bacteria greatly.
However spending a few seconds flowing through a pipe, I’m not so sure that will kill much, but if it sits in the pipe, well then it likely would.

[a64pilot]

Originally Posted by CarinaPDX

Edit: When choosing filter elements do pay attention to the required pressure: particularly the carbon block filters need decent pressure to drive water through them at a good rate.

Greg

You don’t want to push water thru one quickly, not if your trying to absorb odors and tastes, the slower water flows through the filter, the more the carbon will absorb.
When I fill my tanks at the slip, I trickle the water in so that it takes half a day to fill up, that removes more chlorine then if I blew it through as fast as it can flow.
I really ought to get a “Big Blue” canister and use the 4.5”x10 cartridge as opposed to the 2.5” I’m using now.
Maybe if I Used two of them, I could fill my tank as fast as the water will flow? Cause of course dribbling in the water isn’t wha they want you to do at the fuel dock, so I just use my watermaker, but I hate doing that in the ICW.

[CarlF]

I think it helps to divide this problem up:

1) Is the water going into the tank safe and taste good?
2) Once in the tank, does it stay that way?

For the first point - is the municipal tap water where you cruise safe? If not, get a watermaker.

Your new boat is big enough that a watermaker is worth considering even if the shoreside water is safe. It is such a joy to not worry about water on cruises. Long showers. No yelling at guests about water usage. And the water tastes much better than anything ashore - including bottled.

If the shoreside water is safe but tastes a "little" bad, that's easy to fix with a filter. And a filter will take out any chlorine taste. I used to use a Seagull but filter technology has improved while Seagull has stayed the same with a very high price. There are now better filters available for much lower cost. I use a Pentek FloPlus 10 that meet the new US NSF/ANSI 53 standard (Seagull doesn't). I expect there are similar EU standards. The filter cartridge costs about $15 and lasts a long time.

--- Keeping the tank clean:

There's just no reason to have unsafe water in your tank.

Getting a new boat means you can start right. Do a chlorine treatment as suggested when you take delivery and then once a year. Keep it clean by not letting the water sit too long. I always empty and refill my water tanks every three weeks (or immediately upon getting on the boat if it has sat for more than three weeks). This is the single best way to keep the tanks clean. If you fill with tap water, the chlorine in that water will kill anything that was starting to get going in the tank. If I am only using watermaker water (which has no chlorine) I add a bit of bleach once every three weeks. Get a pack of pool chlorine test strips. Most municipal drinking water is about .5-1 ppm chlorine. A swimming pool is about 3 ppm. 1.5 teaspoons of bleach per 100 gallons is 1ppm. As others have said, use your own hose not the marina hose.

If you do the above, there's really no reason to have a UV light. It won't make the water taste better and your water is already safe. A problem with UV lights is that most (all?) have to be left on all the time. If you turn the bulb on and off it burns out quickly. Small ones only draw 8-12 watts but that adds up over 24 hours. Why have another battery drain unless you really need it?

[a64pilot]

Originally Posted by Rumbottle

I've been using the same tanks for 39 years. If you can fill the tanks with drinkable water and add a few crystals of potassium permanganate ("Condys Crystals") you wont have any problems. Put too many crystals in and the water turns purple

As a kid I loved that stuff, filter pure ammonia though it and when it dries it’s a pressure sensitive explosive.
Put a crystal or two in a glycerine “pill” with corn starch and you have a snap cap that explodes when it’s shocked.
Just don’t forget and play football with a Sucrets box full of them [emoji23]

[cj88]

I have always been quite curious as to why it appears that Americans seem to need so much bottled water and hand sanitizer. It might just be an erroneous perception I have built up over time or maybe it is a pretty bad environment to live in. I've never had a problem with drinking from a tank although a carbon filter might help the taste sometimes and rainwater is great. Not all microbes are bad either but I suppose marketing is about creating a problem and then selling the solution.

[CarlF]

CJ88 - While I agree with you on the US fixation with hand sanitizer - I see much more bottled water used when I travel in Continental Europe than in the US. Most Americans drink tap water at restaurants. In European restaurants you risk a funny look from the waiter if you ask for tap water.

[motion30]

I drink 100% of my water out of my storage tank. They are filled from my water. My water is cleaner than bottled water

[Maka]

I have 4 ea. 25 gal water tanks. Total 100 gallons.

We drink water unfiltered from these tanks.
Once a year I empty, flush with lots of Clorox and refill my tanks with potable water in a marina.
While cruising if I distrust a water source it goes into a dedicated tank and used for cleaning only. No cooking or drinking.
The only water I buy and carry on board is for topping off lead acid House battery when needed.

[wcapital]

Originally Posted by Dockhead

I've been drinking boat tank water since practically since I was born, and not dead yet.


Last 10 years with a Seagull IV filter.


Humping bottled water to a boat is just nuts in my view. Wouldn't ever do it, personally.

Not to mention the idocy of all that plastic to keep filling up the world's landfills (and oceans)...

[wcapital]

A little bleach in the tanks, regular cleaning and a Brita filter pitcher has worked fine for us.

[grecko]

I've been drinking water from our tanks and that's because I know the source is safe.

[CassidyNZ]

We have no municipal water in our home. Have been living off tank water gathered off our roof for 7 or 8 years now. Tastes great, never have any problems. Luckily my local marina collects water exactly the same way, off their roof. They take it one step further with UV irradiation to make it safer. We fill out tanks with marina water. Our boat hasn’t seen chlorine for a decade or more.

With no chlorine in our boat water I know I can do my fresh-water flush of the watermaker without any worries re trashing the membranes.

But despite all that, my wife still carries a dozen plastic bottles of commercial water that cost 5 times what our diesel costs - criminal shame IMHO.

[clownfishsydney]

Best thing is to keep water tanks isolated, only use one at a time. Then fill only one if possible. This way if you get poor quality water, then you have not ruined all your water. Like others, I have never used filters (although we do have watermaker which is used when needed) and most water probably has come from shore.

[Mike OReilly]

Originally Posted by desodave

... "1 cup (8 oz) of household bleach per 10 gallon"


Mike, that sounds like an incredible amount of bleach to use. I have an 80 usg tank and use 1 1/2 cups of bleach to shock it, not 8 cups. One public health agency, Yukon Health , recommends 1 cup for every 50 imp gal for an inaccessible potable water tank. I've seen similar recommendations on on RV sites.

This comes from the queen of yacht sanitation systems. It has worked for us so far, but I’m not a chemist, so can’t say whether a lesser amount would be as effective.

[ben2go]

Pure water can kill you.


Source- Pure Water Can KIll You | I, Science


Article

Drinking absolutely pure water can kill you. All the water we normally drink – from taps, from bottles, from the garden hose – contains impurities which affect a property of water called tonicity. This is the ability of a solution to draw or repel water from ajacent solutions when separated by a membrane. Solutions that are hypertonic gain water, while hypotonic solutions lose water. Drinking water, which we usually think of as pure, really contains a whole mess of salts and sugars which make it slightly hypertonic. They also give water its taste. The cytoplasm in the cells of your body also have a tonicity. So, when they are exposed to hypertonic solutions, the cells themselves lose water and shrivel up. When they are in hypotonic solutions, they gain water, swelling up and bursting like a balloon. Absolutely pure water -with no impurities at all – is the most hypotonic solution. So, if you drink enough of it, your cells will start absorbing water. This disturbs the balance of electrolytes (electrically conductive ions) in your body. This is most seriously a problem in the brain, where water poisoning can lead to brain damage, coma and even death.