Treating Fresh Water

[Baggins]

We have been treating water with bleach and were told that it can be corrosive to aluminum tanks. We were told that iodine is preferable. Does anyone have any information about treating with iodine or how to manage on board water storage keeping it safe and clean.

[rivonia]

In our oppinion just leave it well alone. After sailing extensively around the globe over the past 40 odd years. We have never treated any potable water. If the water is not potable then we buy water that is.

Good health!

Peter

[solovenus]

I agree. Potable water untreated ensures that your resistance to bacteria is unaffected by water purification treatments. Leave well alone and the taste is also unaffected.

[GordMay]

Greetings and welcome aboard the CF, Baggins.

[HopCar]

I use Clean Tabs to purify my water and Puriclean to clean my tanks and water system. They are a different form of chlorine than bleach and are non-corrosive.
Read the FAQ section for an explaination.
http://www.cleantabs.co.uk/default.htm
My company is the US distributor and you can order them here: http://www.hopkins-carter.com/aquaclean.html

[rebel heart]

Stainless tanks, I always use a bit of bleach. It's not about "treating it" as much as not letting brownish-red algae grow in the tank. Really only a problem when the water is about 65f, but that's sort of the water you want to be in all the time.

Five tablespoons is fine (for ~100 gallons of water). A little goes a long way for what we're trying to accomplish.

[GrowleyMonster]

I use a little bleach. I also use one of those cheapie filtering pitchers for actual drinking water, where the taste is important. Letting chlorinated water stand for a day will allow all chlorine to evaporate.

[Jsol]

Originally Posted by HopCar

I use Clean Tabs to purify my water and Puriclean to clean my tanks and water system. They are a different form of chlorine than bleach and are non-corrosive.
Read the FAQ section for an explaination.
http://www.cleantabs.co.uk/default.htm
My company is the US distributor and you can order them here: http://www.hopkins-carter.com/aquaclean.html

Glad I ran across this. I've been looking for Puriclean for a couple of years with no luck. I haven't been able to find it anywhere until I ran across your post! Will be ordering some shortly....

[Teknav]

Unless you're going to a place that has a Cholera epidemic, do not add chlorine/bleach to the water; fluorine is a better alternative, if you can find the tablets. As an alternative, adding half a bottle of RUM to a full water tank may not be a bad idea. Rum is available for sale everywhere, except in strictly muslim countries. Anything cooked using this water blend, will taste yummy...err...rummy! The alcohol in rum will retard bacterial growth in the water. Use an alternate water source for the kids, if you have children on board. Mauritz

[GordMay]

Originally Posted by Teknav

Unless you're going to a place that has a Cholera epidemic, do not add chlorine/bleach to the water; fluorine is a better alternative, if you can find the tablets ...

I've never heard of fluorine used as a potable water disinfectant. Can you support that opinion?

[jnrdafoe]

Check out GET RID OF BOAT ODORS by Peggy Hall at Seaworthy Publications. She covers the water systems on a boat at both ends. She describes a "shocking" of the fresh water system. Lots of great info for for eliminating head problems that cause odors.

[sestina]

Manually clean the tanks when you feel very bored. Opaque, ie non-see through pipework and have drinks that don't taste of swimming pools.

[Bill_E]

I'd really like to know the chemistry of Clean Tabs. I'll have to look it up somewhere. Usually one uses the oxidizing power of hypochlorite (bleach) to kill bacteria, mold, algae, etc.

There used to be iodine and bromine treatment systems that backpackers would use. I've never looked at the chemistry of those systems but if they rely on hypoiodite (or hypobromite) then the reactions with aluminum would be similar to hypochlorite. Maybe a little slower.

I also have aluminum tanks and have worried a bit about the problem. Normal, chlorinated city water supplies will slowly react with the aluminum. To avoid that problem I use a relatively inexpensive carbon filter with hose fittings on my hose whenever I fill from the "tap" at marinas. I also ascribe to the idea that you never put non-potable water in your tanks. Then you shouldn't have a big problem.

Peggy Hall does have excellent descriptions of keeping all of your water systems clean. In my opinion she recommends shocking too often. If I recall she recommends it once a year. If you don't do anything silly I think every two to four years should be enough. The main thing shocking does is to clean out the hoses and fittings because that is probably where algae or fungi will grow.

I haven't shocked my system in five years but am preparing to do it this year. I will use hydrogen peroxide to shock it. It's a lot more expensive than bleach (still not that much) and a whole lot harder to obtain. But it won't react with the aluminum. It is an excellent disinfectant. The final "product" is oxygen and water so it leaves no residue except, hopefully, dead bacteria and algae. There are many people who actually think that one should drink H2O2 for health reasons.

Bill

[svtrio]

This is an interesting topic and a cursory glance at hydrogen peroxide vs bleach for treating drinking water proved to be a worthwhile Web search. The anecdotal reports were legion ... but I came away convinced that hydrogen peroxide wouldn't be my choice for treating drinking water.

I have captured below some info from Wiki about bleach for treating water; it succinctly echoes other science-based info I read, including some important tips and a couple of questions that invite more research:

Antimicrobial efficacy

The broad-spectrum effectiveness of bleach, particularly sodium hypochlorite, is owed to the nature of its chemical reactivity with microbes. Rather than acting in an inhibitory or toxic fashion in the manner of antibiotics, bleach quickly reacts with microbial cells to irreversibly denature and destroy many pathogens. Bleach, particularly sodium hypochlorite, has been shown to react with a microbe's heat shock proteins, stimulating their role as intra-cellular chaperone and causing the bacteria to form into clumps (much like an egg that has been boiled) that will eventually die off.[8] In some cases, bleach's base acidity compromises a bacterium's lipid membrane, a reaction similar to popping a balloon. The range of micro-organisms effectively killed by bleach (particularly sodium hypochlorite) is extensive, making it an extremely versatile disinfectant. The same study found that at low (micromolar) sodium hypochlorite levels, E. coli and Vibrio cholerae activate a defense mechanism that helps protect the bacteria, though the implications of this defense mechanism have not been fully investigated.[8]

In response to infection, the human immune system will produce a strong oxidizer, hypochlorous acid, which is generated in activated neutrophils by myeloperoxidase-mediated peroxidation of chloride ions, and contributes to the destruction of bacteria.[9][10][11]

Disinfection

Sodium hypochlorite solution, 3-6%, (common household bleach) must be diluted to be used safely when disinfecting surfaces and when used to treat drinking water. When disinfecting most surfaces, 1 part liquid household bleach to 100 parts water is sufficient for sanitizing. Stronger or weaker solutions may be more appropriate to meet specific goals, such as killing resistant viruses or sanitizing surfaces that will not be in contact with food. See references for more information.[30][31]

In an emergency, drinking water should be treated by boiling for 1–3 minutes, longer at higher altitudes. If boiling is not possible, water can be chemically treated with a ratio of 2 drops of plain liquid household bleach (5-6% sodium hypochlorite solution) per liter of water or 8 drops of bleach per gallon (3.79L) of water; 1/2 teaspoon bleach per five gallons (19L) of water. Do not use powdered bleach, or bleach with scents, cleaners or other additives. Do not collect water for treatment from flood waters or other potentially contaminated sources. If water appears dirty or cloudy, let it settle and/or filter the water before adding the bleach. Let treated water stand covered for 30 minutes. If water is still cloudy after filtering, double the amount of bleach used. If the water is very cold, either warm it before treatment or double the treatment time. Treated water should still have a slight bleach odor after treatment. If it does not, repeat the treatment. If no bleach odor is evident after a second treatment, discard the water and find a better water source.[32][33][34][35] Inappropriate dilutions of bleach can endanger your health.

Roger

[boatman61]

Hi Baggins... Welcome to CF.
I don't treat potable water either... in my travels only two places I've been has the water been crap... Oriental, NC where the water was brackish and by 1000miles into the Atlantic large growths started popping outa the tap... solution... fill a 5litre jug and let it stand... drain off the clear water after an hour and the remaining 2-3litres went over the side..
The other was Nuku Hive where the water was green... our tanks were dry so bought some store water and made a rain catcher for the hop on to US Samoa...made it with jugs to spare... it pissed down everyday for at least 2hrs...
By the way... I don't drink unboiled water... and the boiled is only used with addatives... coffee n rum...
White vinegar works well...