galvanized water tanks are they safe

[elpea]

Hi I have a galvanized water tank fitted to my van, does anyone know how safe they are for drinking water?

[Jennison]

The old std country tin water tank is made of gal, and it is only in the last 10 /15 yrs that they have come with a food grade plastic liner stuck to the inside. Probably more likely to have side effects from the plastic liner in a modern one for all we,d know I imagine jennison

[Don Ricardo]

Hi Elpea,

I think most water tanks in V V's were galvanised iron. Certainly the two tanks in our van are gal.

There are no problems with drinking from them - after all the traditional round water tanks used to collect rainwater on farms and around houses (before they went all plastic and trendy) were galvanised iron as well.

One tip - make sure you empty the water out of the tank at the end of your trip, otherwise next time you will find (a) that the water is rusty and not very palatable, and (b) you've got holes in your tank where it has rusted through.

Don Ricardo

[Deleted]

Hi Don
I beg to differ about emptying gal tanks when not in use. It is not the water that rusts the tank . It is the moisture and air that rusts the tank.

If a tank is left full to the top with no air in there it will not rust.
Think about all the stuff that has been brought up from sunken ships. The corrosion process is accelerated as soon as the air hits it.
Maybe if the filler lid is left off the tank and the tap left in the open position it will allow a flow of air through the tank and prevent condensation from forming and inducing rust.

I had a water tank in "Just Croozn". The water was always of drinking quality until i drain the tank after a trip away. The van sat for 3 months and i filled the tank up before we took off for the weekend. When i went to fill the sink with water it came out orange.
At the time i asked questions on the forum about what to clean it with. I got repies with anything from CLR to Vinegar being the magic cure. always had trouble with it after i drained it. But from memory i had left the lid on an tap shut . Hence locking in moisture / condensation to spark off the corrosion process.

I have another tank here that "prettylittleblackbird" is buying off me. I bought it at a swap meet and the insides of it is perfect. Hasnt had water in it for years and is totally rust free. Probably becuase it came from way out west and has been dried out thoroughly.

I have never had a problem with the drinking quality of the water in these tanks.... up until the time i drained that tank in my first van.In fact i reckon the water tastes better than some of the stuff ya get out of the taps at caravan parks around OZ.


Hope this helps
Reddo

[builderdes]

Reddo, You Are Right About Exposure To Air Accelerating The Corrosion Process,Also The Modern Galvanised Iron Only Lasts Ten Years Tops,A Good Mate Of Mine Restored A XP Falcon Futura About 15 Years Ago That Had Water Sitting On The Floor Pan For Years Before He Bought It,He Is A Old School Panelbeater By Trade, You Know, He Knows How To Use A Hammer And & Dolly Properly,Also He Explained To Me That Exposure To Air &Then Exposure To Moisture Will Rust Metal Really Quick.

[minicamper]

Elpea,

I'm thinking that your angle on the question was more about what happens to water in the tank, rather than rust starting and getting in the water. Were you concerned about leaching of chemical/metals from the the zinc oxide?

Plastics may well be food grade, but i have seem recent research on the molecules that leach from plastic containers and food wraps into the food and water, especially when frozen or heated.

I'd go with better the devil you know. Gal tanks have been around since day dot. All the rust preventative comments above are correct, the only thing I'd add is to change the water left in the tank everynow and then, to keep it "fresh"

[elpea]

Hi all and thanks for all the comments , I was talking to my dad who was the 2nd owner of the sandrover van. we think it is about 1968 vintage, anyhow I asked him what he did with the tank, and he used to empty the tank. I am planning to fill the tank this weekend to see if there is any rust. it has been sitting around empty for about the last 30 years sealed. the outside of the tank appears to be in good order. I will keep you posted.

elpea

[Don Ricardo]

Hi Reddo,

You don't have to beg to differ. I agree with you regarding the combination of air and moisture in the tanks, just didn't express myself fully. I was working on the unspoken assumption that when we arrive home from being away, the tank is often only partly full, and if it isn't emptied then that's when the rust problems start. I'm speaking from experience here unfortunately... (A bit over 30 years ago though, and I haven't done it since, so it shows that I do learn some things! )

You are probably right about corrosion being prevented if the tank is ventilated. The galvanised tanks at home when I was a kid were never full and never airtight and they didn't rust out, nor did the tank which I used as a swimming pool in the back yard. However the caravan tanks with the lids screwed on with just a small air hole in the lid did rust out in quick time.

Thanks for picking me up on my what I said.

Don Ricardo

[elpea]

Well I managed to get the drain bung out of the botton of the tank with much umhing :'(and arhhing . No rust to be seen only a fine layer of white residue on the plug. Filled tank and drained & filled again. looks like water! tastes Like Water! Thanks once again to all, your help was extremly helpful.

Elpea!