Water Quality In Tanks and Watermakers

[Nemo55]

Plastics and Fiberglass tanks,,,,,,all plastics contain "Esters" which is a form of sugar amongst other things,,,so it is reasonable to expect Algae to grow in such a tank if left untreated. Motor-homes have the same problem,,,which is why Stainless steel is a better container.

[Lagoon4us]

Originally Posted by belizesailor

Well, this is a much debated subject... I am quite familiar with them in terms practical experience and to a lesser degree in terms of popular opinion. My 2c on aluminum tanks:

The debate over aluminum tanks generally gets divided into two camps: corrosion and health.

The corrosion issue is easy to address if the tank is properly built and installed (See Calder and others on the right way to do this). Under those assumptions, the service life can be quite long. For example, my previous boat had both aluminum water tanks and fuel tank. These were the original tanks as installed in 1984. When I sold the boat in 2000, these tanks were still in good condition. I am OK with a 16+ year service life.

(Also had an aluminum holding tank on that boat...way bad idea due to corrosion issues from exposure to waste water)

My current fuel tanks, custom aluminum, were installed in 2002 because I did not like the design of the original tanks. They are still in excellent condition, 10 years later. Although, I do plan to physically pull them out for inspection in the next year or two just to make sure (fortunately this is relatively easy to do on my boat, as it is with the water tank too).

Note that both my fuel and water tanks are installed high and dry on the bridge deck of a cat (bilge water being one of the most often sited causes of catastrophic corrosion).

Health. Not my area of expertise, but my understanding of current research consensus: The much publicized potential link to Alzheimer is now considered by researchers as highly unlikely. In terms of overall health, the consensus appears to be that aluminum poses no significant heath risk unless coupled with other health issues, certain medical treatments, or radical exposure levels. I'm OK with too.

That said, I would prefer rotomolded polypropylene tanks for water and waste (I do currently have them for waste), but a new rotomolded water tank was not practical at the time.

Although, even with plastic tanks you are not free from the health debate, as there is much recent speculation about the link between health issues and the plethora of various plastics we use in our modern lives.

Anything else about aluminum tanks that concerns you?

Being a metalworker i installed them in my mono, i would fill using chlorinated water then during a large rainfall i topped up with rainwater. After a week the water had a smell ( we had a carbon filter) so i added chlorine/water purifier tablets.

The chemical reacted badly to the ally producing a white powder, bad taste and eventually that concoction turned to a gel.
I saw it as either a flouride/chlorine/purifier reaction to the ally..... It was off!

[belizesailor]

Originally Posted by Ex-Calif

... I would consider a Y valve on the watermaker output....

Very handy to have for a variety of uses -- not only for diverting water to jug storage if you want, but also will come in handy for testing and troubleshooting of your water maker.

When I see the price of bottled water I also consider diverting to bottles, put a fancy label on them, and sell them for 50% of their typical retail cost ($1 for a bottle of water -- geez!). With the cost of the water maker amortized over 5 years my cost per gallon is about 2 cents -- nice margin!

[belizesailor]

Originally Posted by Lagoon4us

Being a metalworker i installed them in my mono, i would fill using chlorinated water then during a large rainfall i topped up with rainwater. After a week the water had a smell ( we had a carbon filter) so i added chlorine/water purifier tablets.

The chemical reacted badly to the ally producing a white powder, bad taste and eventually that concoction turned to a gel.
I saw it as either a flouride/chlorine/purifier reaction to the ally..... It was off!

Yes, I have read about fluoride/chlorine reactions with aluminum, but never had the problem myself. Maybe just lucky on chemical levels vs alloy types. My tanks are usually filled via the water maker so no issues with fluoride/chlorine reaction there. Also, not much fluoridated (?) water here in the NW Carib. Just filled from my well here at the house....beautiful pure natural water...zero chemicals...soft as a cloud (comes out of the ground at only about 10 ppm!).

[sarafina]

Originally Posted by belizesailor

For example, I have a glass tank at my guest house and it is just fine, but it is coated with sealant inside the tank. However, have been aboard a few boats where you can really taste the epoxy -- probably not real healthy for you either.

Hi,
Do you know what kind of sealant?

Our 45 year old fibre glass tank has small areas where the fibreglass has degraded and there are funky brown spots that do not come up with cleaning. I want a way to seal the tank again and thought a sealant might work. Any ideas? We have looked into resin/epoxy and not found any easily accessible product for consumer use, just high speed professional coatings for commercial applications (an applicators).

[DeepFrz]

Call a paint distributor near you and ask for information on "Food Grade Epoxy Tank Lining Paint". They are widely available.

Here is one product from 3M
http://multimedia.3m.com/mws/mediawe...ating162PW.pdf

[Irish rambler]

There's lots of differing views on tackling the same problem, personally I draw a glass of water from the supply, hold it up to the light and taste it before filling.
To clean water tanks economically, completely disolve 4 tablespoons of Bi carbonate of soda in a jug of hot water, add it to your tank as you fill, let it stand for 24 hours, empty the tanks, refill with clean water and there's no after taste, if you add 1 tablespoon of disolved Bi carbonate of soda to each tank, each time you fill, it will keep your tanks clean.
I'm not a great fan of water filters because if you think about it, all water has to pass through any accumulated crud in the filter.
Good Luck.

[Me-and-Boo]

Having lived off and on in situations where a tank was the source of water I can talk about "tank taste". Unless you are living a great life and have wonderful water tanks, you are going to have water that is not like the stuff that comes out of faucets at home.
It is probably clean if you have tossed in some bleach occasionally, but it has a bite to it or an off taste. That is "tank taste". You can spend a lot of time and money fighting it or you can do some additive things.
The first is to add an inline water filter. Those work.
The second is to learn to like it. That does not always work.
The third is to mask it. As kids we had a lot of Kool Aide in ours. Double up the dose and it is okay. Or as an adult there are other additives short of antifreeze that can help the stuff.
Completely filling and emptying your tanks can go a long way to keeping the water less "tasty". But, when it does not and you do not have the up front cash to buy and install new tanks, it is time to work with alternatives.

[sarafina]

Originally Posted by DeepFrz

Call a paint distributor near you and ask for information on "Food Grade Epoxy Tank Lining Paint". They are widely available.

Here is one product from 3M
http://multimedia.3m.com/mws/mediawe...ating162PW.pdf

Honest we have done that and only gotten contacts with industrial installers. No one who sells for small diy applications.

Has anyone actually found a place to get the stuff and done it?

[Therapy]

Originally Posted by sarafina

Honest we have done that and only gotten contacts with industrial installers. No one who sells for small diy applications.

Has anyone actually found a place to get the stuff and done it?

There was a thread here a looonnnngggg time ago where the OP was directed to a product that was a diy.

I know there are products for gas tanks. It is all epoxy. It does require you to have the tank out so it can be "rolled" around to evenly coat the walls.

[Therapy]

Amazon.com: Interlux Interline Epoxy Tank Coating 92510925A: Home Improvement

Epoxy Coating Comparison Chart - Sherwin-Williams Protective & Marine Coatings

You are right about it being "industrial" though.

[Trekka]

Originally Posted by sarafina

Our 45 year old fibre glass tank has small areas where the fibreglass has degraded and there are funky brown spots that do not come up with cleaning. I want a way to seal the tank again and thought a sealant might work. Any ideas? We have looked into resin/epoxy and not found any easily accessible product for consumer use, just high speed professional coatings for commercial applications (an applicators).

I have the same problem on my tanks, which are built into the hull as part of the hull/sole bonding. So no removal possible. There is a fellow on the CSY owners forum who did just this task of epoxying inside same tanks as mine. His name is Dag, and I am sure you can find his info by looking around there. I have also been given some leads on a local epoxy company that does custom brews and made up such a batch for another sailor a few years ago. I will be contacting them to see if they will still do this.