Water tank cleaning

[BODs SR2]

Unfortunately my fresh water has developed an unpleasant odour. Can anyone recommend a cleaning substance/method to sterilise it all. Thanks

[GUMPY]

Milton tablets are your friend.

Empty tank, drop in several tablets, pre mixed if you can't drop them straight in. Fill tank.

Water is ok to wash shower etc but you will need separate drinking water. Use water as normal after a tankful or so smell will be gone.

[JoeC]

I think with Milton you can use the tank without rinsing once you have put the tablet/liquid in the water and then drained it off. Other brands you then have to rinse the tank once or twice. But as GUMPY says, it does leave an aroma albeit still drinkable. Think baby bottles etc. - you leave them to soak and then use them straight out of the Milton dilution.

[Sea Dog]

I use Elsan Fresh Water Tank cleaner which is purpose made for the very job itself. Pop it in a full tank, draw some into the pipes by running each tap. Drain and refill the next morning and you can then drink the water. (Obvs, read the instructions for yourself).

[jonathanA]

I've always just used THIN bleach, must be cheapo THIN (not thick) bleach - lob some (not very much) in the tank, fill tank, draw through all taps/shower head and leave for an hour or two and then drain and refil tank (more than once if needed) , flush through until you can't taste/smell the bleach job done. 

 

using milton or proper tank cleaner seems easier if more costly !

 

there is a recommended so many ml per litre of tank for thin bleach, I seem to recall is quite a small amount. 

 

I find it easier to drop an spare bilge pump in the inspection hatch rather than run the water pump for hours to drain the tank. a 500GPH bilge type pump is far faster than any jabsco/shureflow water pump. 

[BODs SR2]

Thanks peeps. Will give it a go. 

[Tonka]

Puriclean seems to be proffered by the caravan brigade and is what I used on my daughters caravan which she bought secondhand this year

[cuthound]

7 hours ago, jonathanA said:

I've always just used THIN bleach, must be cheapo THIN (not thick) bleach - lob some (not very much) in the tank, fill tank, draw through all taps/shower head and leave for an hour or two and then drain and refil tank (more than once if needed) , flush through until you can't taste/smell the bleach job done. 

 

using milton or proper tank cleaner seems easier if more costly !

 

there is a recommended so many ml per litre of tank for thin bleach, I seem to recall is quite a small amount. 

 

I find it easier to drop an spare bilge pump in the inspection hatch rather than run the water pump for hours to drain the tank. a 500GPH bilge type pump is far faster than any jabsco/shureflow water pump. 

 

The correct ratio for disinfecting water tanks is 500ml for every 100 litres of water.

 

 

[Sea Dog]

1 minute ago, cuthound said:

 

The correct ratio for disinfecting water tanks is 500ml for every 100 litres of water.

 

 

Really? Two and a half litres of bleach in my tank sounds a bit excessive. 

[cuthound]

5 minutes ago, Sea Dog said:

Really? Two and a half litres of bleach in my tank sounds a bit excessive. 

 

Although this site is American, I don't suppose their disinfection rates are much different to our 

 

They say 6% bleach, so 600ml per 100 litres..

 

https://waterandhealth.org/safe-drinking-water/how-to-disinfect-water-storage-tanks-using-chlorine-bleach/

[Sea Dog]

2 minutes ago, cuthound said:

Although this site is American, I don't suppose their disinfection rates are much different to our 

 

They say 6% bleach, so 600ml per 100 litres..

It might well be right, it just sounds a lot. I wonder whether that allows for the usual thin bleach in the UK being 5% sodium hypochlorite? Anyway, the Americans bleach their chickens too you know - bit free and easy with the bleach in the former colonies if you ask me! 

 

I think I'll stick with the Elsan product where there's less scope for a horlicks with the dosage - nobody likes bleach in their horlicks at any rate.

 

 

[cuthound]

14 minutes ago, Sea Dog said:

It might well be right, it just sounds a lot. I wonder whether that allows for the usual thin bleach in the UK being 5% sodium hypochlorite? Anyway, the Americans bleach their chickens too you know - bit free and easy with the bleach in the former colonies if you ask me! 

 

I think I'll stick with the Elsan product where there's less scope for a horlicks with the dosage - nobody likes bleach in their horlicks at any rate.

 

 

lol, you do know that you are supposed to drain the bleached water and refill a couple of times...

Edited September 4, 2023 by cuthound
To remove a full stop masquerading as a space.

[jonathanA]

2 hours ago, Sea Dog said:

Really? Two and a half litres of bleach in my tank sounds a bit excessive. 

Yeah I agree. Not sure where i read the amount of thin bleach but it was more like 500ml per 1000 litres. Surprised to find the yanks using metric units they've probably got it wrong converting from their nonsensical US gallons. 

[BODs SR2]

On 04/09/2023 at 11:53, BODs SR2 said:

Thanks peeps. Will give it a go. 

The Milton liquid worked a treat. I put it in before refilling the tank so it condensed around the outlet. Next time I’ll fill half way before adding so it gets mixed in better. 

[blackrose]

On 04/09/2023 at 10:41, Sea Dog said:

I use Elsan Fresh Water Tank cleaner which is purpose made for the very job itself. 

 

Really? I just don't think I could bring myself to put anything with the Elsan brand into my fresh water tank. It just doesn't seem right. 😋

[Momac]

On 04/09/2023 at 11:44, jonathanA said:

 

 

I find it easier to drop an spare bilge pump in the inspection hatch rather than run the water pump for hours to drain the tank. a 500GPH bilge type pump is far faster than any jabsco/shureflow water pump. 

Yes it may well be faster 

But I suggest pumping the sterilising solution through the pipework is just as important as the tank. 

 

[jonathanA]

1 hour ago, MartynG said:

Yes it may well be faster 

But I suggest pumping the sterilising solution through the pipework is just as important as the tank. 

 

perhaps if you read the full post and thought about what I said you would see how silly your out of context snippet is  🙂 

[Tonka]

3 minutes ago, jonathanA said:

perhaps if you read the full post and thought about what I said you would see how silly your out of context snippet is  🙂 

Puriclean is designed to be used in the tank and pipe work. Also cleans the hot water tank which is essential if you have a shower

[jonathanA]

47 minutes ago, Tonka said:

Puriclean is designed to be used in the tank and pipe work. Also cleans the hot water tank which is essential if you have a shower

you drink water from the hot tank ? weird.....

[Alan de Enfield]

2 minutes ago, jonathanA said:

you drink water from the hot tank ? weird.....

 

Ever heard of legionnaires disease ? (lives in warm water, particularly showers)

 

It was (is ?) a legal requirement that we had to regularly have the showers at the Golf Club tested and treated.

Can you really catch Legionnaires’ disease from showers?

Legionnaires’ disease is a serious lung condition similar to pneumonia and is caused by Legionella bacteria. While legionella is a bacterium that occurs naturally in water sources around us, it can also infiltrate manmade hot and cold water systems. Fortunately, there are ways to prevent the bacteria taking hold in these systems. However, if certain procedures are not followed, it is possible for individuals to contract Legionnaires’ disease – and yes, this can happen when using an affected shower.

 

 

[jonathanA]

1 minute ago, Alan de Enfield said:

 

Ever heard of legionnaires disease ? (lives in warm water, particularly showers)

 

It was (is ?) a legal requirement that we had to regularly have the showers at the Golf Club tested and treated.

Can you really catch Legionnaires’ disease from showers?

Legionnaires’ disease is a serious lung condition similar to pneumonia and is caused by Legionella bacteria. While legionella is a bacterium that occurs naturally in water sources around us, it can also infiltrate manmade hot and cold water systems. Fortunately, there are ways to prevent the bacteria taking hold in these systems. However, if certain procedures are not followed, it is possible for individuals to contract Legionnaires’ disease – and yes, this can happen when using an affected shower.

 

 

yes and so long as your hot water is stored at 60c or more than that temperature is considered high enough to kill legionnaires according to the HSE 

 

60°C

 

Hot water storage cylinders (calorifiers) should store water at 60°C or higher. Hot water should be distributed at 50°C or higher (thermostatic mixer valves need to be fitted as close as possible to outlets, where a scald risk is identified). Cold water should be stored and distributed below 20°C.14 Dec 2021

 

I don't think some diluted cleaning/sterilising product , further diluted by being drawn into the cauliflower is going to be enough to sort out any shower heads, they'd be better taken off and an soaked in a known concentration of the chosen product IMO.

[blackrose]

I used Milton fluid in my (integral) fresh water tank when my boat was about a year old because I read about doing it on this forum. Since then I never bothered again and 18 years later it's still fine. 

 

If the water started tasting funny I'd probably sterilise it again or just drain it down, open it up and repaint it again.

2 minutes ago, jonathanA said:

yes and so long as your hot water is stored at 60c or more than that temperature is considered high enough to kill legionnaires according to the HSE 

 

60°C

 

Hot water storage cylinders (calorifiers) should store water at 60°C or higher. Hot water should be distributed at 50°C or higher (thermostatic mixer valves need to be fitted as close as possible to outlets, where a scald risk is identified). Cold water should be stored and distributed below 20°C.14 Dec 2021

 

I don't think some diluted cleaning/sterilising product , further diluted by being drawn into the cauliflower is going to be enough to sort out any shower heads, they'd be better taken off and an soaked in a known concentration of the chosen product IMO.

 

Temperature should be enough to kill legionnaires as long as that hot water can get to ALL parts of the freshwater system and there are no "dead legs" in the plumbing which it may not reach.

[Tonka]

1 hour ago, jonathanA said:

perhaps if you read the full post and thought about what I said you would see how silly your out of context snippet is  🙂 

Also why clean the tank and then introduce a dirty pump just to save time

[Machpoint005]

1 hour ago, Tonka said:

Also why clean the tank and then introduce a dirty pump just to save time

 

Dunno about saving time though. There is always another job to be done on a boat whilst waiting for the s-l-o-w system pump to empty the tank.

 

Even if it's only sitting on your arse doing the crossword. 

 

 

[Sea Dog]

10 hours ago, blackrose said:

If the water started tasting funny I'd probably sterilise it again or just drain it down, open it up and repaint it again.

Or even just drain it down and refill it with fresh chlorinated water from a water point. Sometimes water that's been hanging around a while just needs replacing.