Cleaning out flexible water tank and manual cold water system

K

kiddieduptoo

New Member
Joined
3 Feb 2007
Messages
7
Visit site
Dear forumites,

The Jeanneau trailer sailer that I bought last year has a manual cold water system that has not now been used for two and a half years, and was left full of water by the previous owner. The Plastimo flexible water tank is fed from an inlet on the deck, and feeds a manual cold water tap in the cabin.

What is likely to be necessary to clean out the system to make the water drinkable?

My thoughts are either to flush out the existing water a couple of times and then add some Milton sterilising solution and leave for a while, ot to pump out system, remove the flexible tank and either clean it out or replace it. The drawbacks with the latter two options are that the tank inlet and outlet hoses are very well secured with whipping, and are not very accessible under the cockpit. Also, if tank removed, the rest of the system would still need to be cleaned out.

Any thoughts would be much appreciated.

Thanks
Mike
 
Unfortunately, whatever treatment you apply the water will taste of 'tank water'. It's really a case of finding a product that you can put up with the aftertaste of.

From experience, I recommend doing away with it completely, and hold all your water in 5 litre containers. Many many adavantages over a single large tank, and all you lose the advantage of having water coming out of a tap.
 
Hello
I usually go down the milton route every winter, this cleans the tank and the hoses. I still get the odd bit coming out so last winter I went to my local and asked if they would let me have some beer line cleaner this worked a little better, if you do this don't leave it in the pipe/tank over night 20/30 mins should be enough, and it's very important to dilute with the reccommended amounts of water. This winter I am going to try some cold water descaler as well.
 
I would pump it out, refill it and pump it out again, if you can stand all that manual pumping, then refill and dose with Milton at several times the recommended dose rate for treating drinking water (the figure is on the bottle) make sure some of the treated water is pumped through the pipework. Let it stand for a while, a few hours or over night, then pump it out again give it a quick flush and refill with water to use. There will probably still be enough Milton left behind not to require any more but subsequently you can dose with Milton at the recommended rate to keep it all sweet. You may even have to pump out again if you find too much Milton left.

You do not say if it is a pillow tank, that collapses as the water is drawn off or whether it is a shaped and vented tank that does not collapse. If it is the former you will not need to completely refill it at each stage especially if you can get at it to sqeeze the air out and slosh it about a bit. If it is a shaped tank then you will have to completely refill it at each stage.

Some people are prepared to risk drinking any nasty chemicals and impurities in household bleach and use that in order to save a few shillings but you will have to work out your own dosing rates. I would ensure that I had rised it all out if I used that and I would not use it to dose the final water supply.

Chloramine T was recently advocated by one forumite and a search over recent weeks should find that thread. It is expensive though

There are also proprietary tank cleaners available from chandlers at a price.

On reflection you might as well dose the water still in the tank before pumping it out and also the flushing charge.
 
[ QUOTE ]
Unfortunately, whatever treatment you apply the water will taste of 'tank water'. It's really a case of finding a product that you can put up with the aftertaste of.

From experience, I recommend doing away with it completely, and hold all your water in 5 litre containers. Many many adavantages over a single large tank, and all you lose the advantage of having water coming out of a tap.

[/ QUOTE ]I disagree. I sail on lots of boats and lots of them don't taste of 'tank water'. Flush it out a couple of times, add some milton and flush again. Taste the water and see how it is. Flush a couple more times if its still not good. If the water is fresh it should be fine.

We have one of those activated carbon filters on our main tap and the water tastes of nothing at all - like all good water should.
 
Plastimo flexible tanks...

From my experience of Plastimo flexible tanks, I'd say that it's very difficult to clean the inside effectively, even if you remove the bladder from its outer casing. I've had some success with a hosejet, but it's not very easy. As a result (and especially as your tank is difficult to access), I'd try the chemical route first.

Whatever you use for the serious cleaning, you're going to have to do lots of flushing out, so I wouldn't worry about the alleged impurities in household bleach. For cleaning tanks, I use the very cheapest supermarket own-brand thin bleach (about 25p a big bottle). You can use Milton, which is basically a very dilute bleach solution, but you're paying for their branding and, as you're going to have to flush it well anyway, it doesn't matter.

However, if the tank is really bad, you might consider using a chlorine dioxide product (eg Aquasol), which is perhaps more effective for water disinfection.

When finally filling the tank with water you're going to consume, it would be a good idea to add some sterilising tablets. I use Aquatabs in mine.

For flushing, don't try to pump it out with your manual water tap - it's easier to just remove the hose from the tank outlet and let it run into the bilge and pump it out from there with the bilge pump.

As John Morris has suggested, a carbon filter is a good idea and is very easy to fit. This will not only improve the taste of the water, but it will also trap the little flakes of rubbish which will wash off the tank sides.
 
Re: Plastimo flexible tanks...

I have a rubber tank and I took it out and thoroughly cleaned it last winter by pumping a lot of water and cleaner through it and pummelling it - horrified by the amount of crud in it. But how much of the water in a boat's tank is ever used for drinking? I use the water in the tank for washing up and for what passes as personal hygene but for drinking and for tea and coffee where taste matters I carry much smaller clear plastic containers of water taken from a real tap and not from the ancient and probably filthy hose at the end of my pontoon.
 
Chlorine based disinfectants are destructive to some flexible tanks, and manufacturers warn against their use. The manufacturer of my tank "Hovercraft Consultants Ltd, Duratank" specifies silver contained in ceramic beads.

"Designed to kill the cause of water contamination rather than treat the symptoms.

The DURATANK water protection system consists of small, porous ceramic beads impregnated with flecks of noble metals. This combination produces ionic oxygen which acts as a powerful disinfectant against bacteria and slime but without the use of chemicals and the associated taste in the water"

http://www.dureflex.co.uk/products/asp/p...asterCategory=n

I make no recommendation, and merely washed out with detergent, at the end of last season.
 
Polyurethane vs PVC...

Your Duratank is made from polyurethane, which can degrade in the presence of high concentrations of chlorine. The original poster has a Plastimo flexible tank - these have a PVC liner, which is very resistant to chlorine attack.
 
Adding to this post, I find the secret of voiding the taste is to ensure all contaminated water is removed: can you enter the tank with a sponge etc to wash the walls with diluted Milton (Boots and other chemists do their own at lower prices - so cheap you don't have to take chances with lavatory cleaner!)

I back the idea of an inline filter - easily inserted - I use the Whale system - the filter lasts a season and costs less than £20 to replace - no taste at all, and well worth it.

Going to tanks is no solution - I started with these and I found them open to contamination as the season advanced, requiring booring washing out etc. Proabably those who use them don't look inside too often and see the green slime build up - and there's no filter remedy with tanks, as with on board storage. No upset tummies here please!

PWG
 
Mike, at £50 for a new one just replace it. Just replaced the Ali tank on Fly By because it leaked with a Plastimo one. You don't want to see what came out of the old tank. We have a plastic taste from the new tank but that should go with a few flushes.

Pete
 
The Plastimo flexible tanks normaly have a tag on the outer bag giving cleaning details .... A vinegar solution is recomended but i cant remember the dilution ratio.
As the inner tanks are larger than the outers (to prevent stress on the seams)if the inner is left in there may be some bits traped in folds so it may be wise to take the inner out. you can now see whats in there but be carefull of the seams if you part fill the inner on its own.
 
Just a few facts. This is not rocket science.

First. Ordinary household bleach (not 'thick bleach') is sodium hypochlorite in a 3% to 5% solution. Check that the bottle says 'suitable for use in water systems' or words to that effect. Brewery cleaning products are the same product, sometimes at higher concentrations. Milton is the same product, but in a <1% solution at many times the price. Sodium hypochlorite is routinely added to drinking water at the rate of about 1/5000 as a standard treatment. Higher concentrations are used in swimming pools.

Next, the routine for cleaning out water systems is commercially well established:

1. Partially fill your system with 5 parts water to one part household bleach (the 3% to 5% stuff).

2. Run this solution through all your pipes and lines so they are full. Leave for about half an hour.

3. Empty the system through your pipes, taps, shower outlets, whatever. Flush twice with a large amount of fresh water.

4. The system will still smell of chlorine. That doesn't matter, but if you wish to reduce this, flush all pipes through with a 1/10 solution of vinegar (only after a good water flush mind) which will release any remaining chlorine ions as gas.

5. Flush and fill. You've done it.

By all means add a spoonful of bleach, a silver or other noble metal pill, or whatever. Even put a filter in line. These steps may make you feel better, but they're unlikely to have any additional effect to the flush you've just performed. Until a month or two has passed.

And to prevent mould growth in the tanks for the future, make sure no light gets in - that's why portable tank storage should always be in black containers.

JimB - still alive after doing this some ten times.
 
[ QUOTE ]
that's why portable tank storage should always be in black containers.


[/ QUOTE ] For portable storage of drinking water food grade plastic should be used so it is a good idea to buy water cariers from a camping shop. They are almost certainly going to be white translucent so to prevent algae growth keep them in a dark locker.

As I only have a small built in tank I always take a supply of fresh drinking water with me in a carrier or two and at the end of a weekend I put what is left in the tank.
 
A small additional note: you can buy replacement inner bladders for the plastimo tanks (though not a lot of places sell them) these cost less than 30 quid.

The reason I know this is I had exactly the same situation as you but when I tried to clean the tank it split because it had become brittle.
We also decided to replace the fresh water pipes, figuring they too would be in a similar state and may not have been food grade - took a few hours but the new pipe only costs about a tenner.

We also replaced the whale inline filter but that was a right pig to do (just cut the old one off in the end as we were replacng the pipe anyway). Can anybody suggest a system for quick connect/disconnect of these things? (we have 13mm flexible hose)
 
You must log in or register to reply here.

Other threads that may be of interest

Refueler
Strange water accumulation ...
Replies
9
Views
333
Refueler
Refueler

Share this page

Top