Cleaning out the fresh water tank...

[alt]

Now I never use the fresh water tank for drinking out of, but I can't help but feel giving it a bit of a 'clean' would would it good.

Normally at the start of season I just fill the tank again and let it run through a couple of tanks, cleaning out the houses/tanks a bit.

Wondering if anyone puts any chemical/solution in there (non toxic of course) to help clean it out? I was thinking some Milton wouldn't do any harm?

 

[PaulGooch]

Now I never use the fresh water tank for drinking out of, but I can't help but feel giving it a bit of a 'clean' would would it good.

Normally at the start of season I just fill the tank again and let it run through a couple of tanks, cleaning out the houses/tanks a bit.

Wondering if anyone puts any chemical/solution in there (non toxic of course) to help clean it out? I was thinking some Milton wouldn't do any harm?

Milton won't do any harm, but if you were drinking it, it's take a good few flushes to get rid of the taste. I'd fill and empty the tank then refill, adding some boots sterilising tablets, disolved in a little water. Leave overnight and thoroughly flush. I see no reason not to drink from the tank if it's clean, we do.

 

[strakeryrius]

I always leave the fresh water tank in the red over the winter, giving it a dose of AquaSol just before she comes out of the water. When she goes back in I put in about 50 litres with a double-dose of AquaSol, leave til next visit, then run it all off through all the taps and shower fittings aboard. Then repeat that a couple of times before a full fill up with normal dosage of AquaSol and start using it normally.

We drink from our taps and clean our teeth with it etc and it tastes fine - although SWMBO still insists on running it through a Brita filter before making tea with it.

 

[CET1]

Milton at the start of the season every year. Just takes time to flush but we can taste the difference after.

 

[RAI]

Bicarbonate of soda solution. Then flush.

 

[Adrianwool]

If you have an accessable inspection point for your water tank, its worth taking off and cleaning out the tank manually before filling at the start of a season. We are lucky enough to have this feature and with a clean sponge its amazing how much grit etc you will find laying in the water tank, (where does it come from?). Half fill tank & run through taps, then refill tank. Have an inline filter on the galley tap which provides 'sweet' enough water for squashes an tea such that there is no nasty taste.

 

[Jane Farraday]

I never drink the water from the tank, preferring to take bottled water on board. I still think it's a good idea though to clean the tank out, because I wash my veg and salads with it. It's important if you use Milton to get the dilution correct, otherwise it could be useless.

 

[alt]

Thanks folks, for convenience i'll just get some Milton. I have a 200 litre tank so will read the back of the label and use whatever is necessary.

 

[VicS]

See also the Milton website, in particular the Camping and Caravanning page

I strongly recommend dosing the initial fill with Milton at the rate specified for drinking water and perhaps water added during the season ... don't overdo it though.

Sterilising a 200 litre tank is going to take a lot of Milton.
I am not keen on using domestic bleach but it is more concentrated and for a contaminated tank it may be necessary to use that at an equivalent dilution.
BUT if you do, use one of the cheap, own brand, non thickened ones and rinse the tank out thoroughly afterwards

 

[Trundlebug]

I've used Milton with great success and was amazed at just how far it went.

Bought a bottle and only used about 1/4 of it!

Originally the water tank had no access hatch, but when I fitted a gauge and had to dill a 3" hole in the top for the sender, I took the opportunity to pump out all the sandy grit in the bottom. Not that there was lots of it, especially for 20 years worth, but better out than in as they say.

Having put a few gallons in the tank with a strong Milton solution I pumped it through the system and left it in the taps and pipework for a while to sterilise everything. It's been great since. We always use the water for squash, tea, everything no problem. Our quality controller is the dog, she wouldn't drink it if there was anything wrong with it so we know it's OK. Can't see the point in having a proper water system, all clean and only using bottled water!

 

[EdWingfield]

potable water dosing and super-chlorination

Yotties usually load water via marina hoses. They should be cautious and assume the water is contaminated with bugs and dose the water at every filling to achieve a background level of 0.2 parts per million chlorine. Tap water is designed to arrive at our taps at 0.2ppm but this concentration will be lost to air as the water is gushed into the tanks.

At the beginning of season I’d advise a super-chlorination of the tank and plumbing. You will need to know the volume of your tank and add enough product to achieve 50ppm concentration when full and it should be run through to work on the entire plumbing system and allowed to stand for 24 hrs. After that time dispose of it and refill with new water dosed to 0.2ppm.

Products for this purpose (ship water) is available but expensive, often with a min order value of £50. Milton also.

As has been advised earlier use the cheapest (unscented) own-brand supermarket bleach, from the label you will find the concentration. Do your maths and add the appropriate amount for super-chlorination or dosing.

If you are unsure, phone the company and ask for technical assistance. The companies are pretty good and you will soon have good guidance for free – but you will be asked the volume of your tank(s).

Finally, if you want reassurance as to the fitness of your potable water it should be sampled by a public health laboratory. If you are operating a business eg. chartering then it will be required. On the Tyne we do it free of charge.

Bicarbonate of soda is not recommended. And nor a dog as a reliable guide to water quality.

 

[Trundlebug]

Products for this purpose (ship water) is available but expensive, often with a min order value of £50. Milton also.

Milton expensive? I was surprised at how relatively cheap it was, for the volume of water it treats. Amazingly economical in use.

From memory it was about the same price as a bottle of Evian (or similar) but treats about 1000 times the volume, or even more... I could be mistaken of course. Bottled water could be the cheaper option (!)

Some good advice in your post though. You may be right about the dog not being the best quality controller, I forgot to mention she drinks out of puddles too.

 

[Major Catastrophe]

I always thought that Milton - Sainsburys does an own brand Milton at a fraction of the price - was just a diluted bleach.

Following practice of what we did in the forces with our water bowsers before the 'exercise season', unscented bleach did the job just as well and even cheaper.

Potassium permanganate was also used to disinfect water.

 

[alt]

Thanks for all the advice folks. I ended up putting in 1l of Milton into 200l of water and let it run up the pipes. I've it left now for an hour or two to do its thing and i'll drain it after dinner, refill with fresh water and let that run though too.

 

[VicS]

I always thought that Milton - Sainsburys does an own brand Milton at a fraction of the price - was just a diluted bleach.

Both are hypochlorite solutions and Milton is a more dilute solution than domestic bleach.

Bleach may contain other ingredients that it may not be advisable to consume. It may even contain some sodium chlorate (as in weedkiller ) as an impurity.

Milton contains only sodium hypochlorite and ( a surprising concentration of) sodium chloride.

Good tip though that JS do their own brand equivalent of Milton.

 

[PaulGooch]

Boots do own brand sterilising tablets too.

 

[Major Catastrophe]

It may even contain some sodium chlorate (as in weedkiller ) as an impurity.

That will explain why the grass never grew under my battalion.

 

[mikehibb]

Edwingfields post sounds just the same as I was recommended by our company's consultant. He have large camps for oil workers and need to make sure our water is OK.

Also as mentioned cheapest bleach hypochlorite (unsented)

I will be doing the same myself in just a couple of days, whoooppeee fly to Turkey tomorrow.

Will then add a couple of milton tabs as I top up the tanks through the season.

We still use bottled water for drinking though, but we normally only day cruise or a couple of days away at max so no probs with carrying extra bottles.

 

[carlton]

Having witnessed a dog on our pontoon merrily licking its rear end before wrapping its tongue around the end of the hosepipe I can assure you that no amount of sterilising product would persuade me to drink the water from that.