Cleaning Fresh Water Tank

[matthewriches]

I need to sanitise my fresh water tank. It is a 600 litre stainless steel square tank that only has an access hole where the sender unit is.

I was thinking of filling it to the overflow with water and some form of disinfectant but what should I be using?

I'd like to do it a few times as it has been sat for 2 years unused.


TIA!

 

[pvb]

Use the very cheapest supermarket bleach, like Tesco Everyday Value Thin Bleach (a staggering 29p for 2 litres). Add about a litre to your 600 litre tank, fill the tank, leave it to stand for a few hours, empty, repeat, empty, rinse with fresh water several times. It's perfectly safe. People will no doubt advise you that Milton is the stuff to use, but it's basically expensive dilute bleach.

 

[matthewriches]

Perfect. Thanks. I did hear about bleach but wasn't sure on exact dilution. To be honest if I give it a good hit, I was thinking of flushing it though anyway a few times with clean water anyway. Just worried about any algae growth over the last few years.

Thanks

 

[Fantasie 19]

People will no doubt advise you that Milton is the stuff to use.

+1

 

[JumbleDuck]

I use Puriclean, with four flushes.

 

[sarabande]

if you want to change bleach to Milton, just add about 1/2 cup of cooking salt to the tank as well.

After a two year 'holiday', I'd make sure that the inlet and outlet pipes and taps are thoroughly cleaned internally, especially where any light has been able to get in.

 

[prv]

I use Puriclean, with four flushes.

I use the same or similar stuff, leaving a strong dose overnight and then flushing it until I can no longer taste it.

I'm sure simple bleach is fine too; I'd just be wary of other things (perfumes etc) having been added. So the advice to pick the cheapest is probably good

Pete

 

[Sandy]

How often do you drink the water from the tank?

 

[prv]

How often do you drink the water from the tank?

In my case, every time I go out. It tastes no different to the water from my kitchen tap.

Pete

 

[nemodreams]

From experience with a flexible tank - with horrible black gunge that I could see easily - ie - I took it home to clean out in the bath - bleach would not touch it, which surprised me !

24 hrs with a double the rec dose of Puriclean and it was spotless - like new !

If you look at the chemical constituent of it its not the same as bleach. Very impressed.

Now - as I seldom drink the water in the flexy tank - every time I top up I add a spoonful of Metabysulphate ( wine making supplies ) Stays squeeky clean - and has the body of a good Burgandy !

 

[VicS]

I need to sanitise my fresh water tank. It is a 600 litre stainless steel square tank that only has an access hole where the sender unit is.

I was thinking of filling it to the overflow with water and some form of disinfectant but what should I be using?

I'd like to do it a few times as it has been sat for 2 years unused.


TIA!

Miltons recommended procedure is to fill the tank with water adding 30ml Milton per 5 litres. Allow to stand for 15 minutes and then rinse out.

For a 600l tank that works out at quite a lot of Milton

Therefore as suggested use a thin domestic bleach ( eg supermarket own brand) Because it is about 2½ times the concentration of Milton approx 1½ litres would be about the right amount to use.

Allow to stand for 15 mins and rinse well.

In future dose the water going into your tank with Milton at the rate of 2.5 ml per 5 litres if you have any doubts about it . The water will be OK to drink after 30 minutes but do not exceed the dose rate or you tea will taste foul.

 

[VicS]

From experience with a flexible tank - with horrible black gunge that I could see easily - ie - I took it home to clean out in the bath - bleach would not touch it, which surprised me !

24 hrs with a double the rec dose of Puriclean and it was spotless - like new !

If you look at the chemical constituent of it its not the same as bleach. Very impressed.

Now - as I seldom drink the water in the flexy tank - every time I top up I add a spoonful of Metabysulphate ( wine making supplies ) Stays squeeky clean - and has the body of a good Burgandy !

Puriclean contains, carbonates, phosphates and silicates in addition to a source of chlorine ( sodium dichloroisocyanurate I suspect)

The winemakers sterilising agent you are attempting to recommend is sodium metabisulfite. It is a source of sulfur dioxide.

 

[nigelmercier]

... sodium dichloroisocyanurate ...
... sodium metabisulfite. It is a source of sulfur dioxide.

I'm glad you mentioned sodium dichloroisocyanurate as it caused me to look it up. I've always assumed it contained the CN group, which rather worried me.

It also worries me that you have turned into an American

 

[Momac]

I used a litre of supermarket own brand sterilising liquid in my 250 litres tank . Cost under £2.
The mix was strong smelling and required a full tank of fresh water flush to clear the odour. I only do this once a year in the early spring . I don't add any treatment on a regular basis as we regularly consume the water between April and October.
In any case I avoid drinking tank water and prefer a separate 5 litre container and draw some fresh mains water .

 

[JumbleDuck]

It also worries me that you have turned into an American

"Sulfur" and its derivative have been the official spellings for IUPAC since 1990, for the Royal Society of Chemistry from 1992 and for school exams in England and Wales since 2000. The spelling "sulphur" was based on a misapprehension: words taken from Greek often turn a "phi" into "ph", but sulfur is not a Greek word and so an "f" is correct.

 

[RichardS]

How often do you drink the water from the tank?

We used to buy bottled water because you can put the bottles in the fridge and SWMBO and the kids like the idea of drinking "pure" water.

A couple of years ago I started refilling the empty bottles from the boat tanks in the dead of night when no-one was around.

Nobody noticed so after a few weeks I told everyone.

We are still refilling those same bottles and everyone is happy.

(Did I mention that I'm a Yorkshireman! :encouragement: )

Richard

 

[vyv_cox]

"Sulfur" and its derivative have been the official spellings for IUPAC since 1990, for the Royal Society of Chemistry from 1992 and for school exams in England and Wales since 2000. The spelling "sulphur" was based on a misapprehension: words taken from Greek often turn a "phi" into "ph", but sulfur is not a Greek word and so an "f" is correct.

We live and learn! I didn't know that. Not sure whether the same message has got through to metallurgy though, all the UK sites I use seem to still use ph.

Back on thread - My water tank is difficult to clean with chemicals and my experience is that cleaning with a brush is far more effective. However, the biggest improvement I made to the taste of tank water was when I changed the 25 year old hoses, transformed it, even when using a General Ecology filter.

 

[VicS]

We used to buy bottled water because you can put the bottles in the fridge and SWMBO and the kids like the idea of drinking "pure" water.

A couple of years ago I started refilling the empty bottles from the boat tanks in the dead of night when no-one was around.

Nobody noticed so after a few weeks I told everyone.

We are still refilling those same bottles and everyone is happy.

(Did I mention that I'm a Yorkshireman! :encouragement: )

Richard

I hope you dont store water in those plastic bottles for any length of time.

http://www.rsc.org/chemistryworld/News/2006/January/19010601.asp

 

[Norman_E]

I would not use any chlorine based product, i.e. bleach or even Milton, in a stainless steel tank. Both my stainless tanks developed leaks that had to be welded, and the most likely reason was corrosion caused by the use of chlorine bleach. If the OP drinks water from the tank then the best solution is to have an access panel cut out of the top of it, and a bolt on cover made. It is not too difficult to do as such tanks are usually fairly thin. A large circular or oval hole needs to be made and a cover plate of thicker stainless steel made about an inch larger all round. Holes need to be drilled at fairly close intervals through cover and tank to bolt it on and to secure the lid. The easiest way is to put bolts in so that they point upwards through the tank and secure each one with a weld. A neopreen rubber gasket completes the job.

To clean it out thoroughly I would use Jeyes fluid, followed by repeated complete filling and emptying with clean water before any is drunk.

 

[RichardS]

I hope you dont store water in those plastic bottles for any length of time.

http://www.rsc.org/chemistryworld/News/2006/January/19010601.asp

Only for a few months at most ..... but the article is claptrap anyway.

Richard
BSc (Hons) DIS (Polymer Chemistry)