Grimey water tank...

[EclairII]

There is some nasty-looking grime in my (one-season-old) Plastimo flexible water tank liner - probably because I got the Aqua Tabs to fill-up ratios all wrong. Because of the inlet and outlet aperture sizes it is hard to get any sort of brush into the interior. Anyone got any tips for dissolving the muck and cleaning out the tank? I've read somewhere that 1:20 vinegar to water is good but I don't want to jeopardise the sealing and nor do I want to flavour my water with vinegar for a year!
Thanks a lot
James

 

[ShipsWoofy]

If you can get the tanks out you can fill them flat on the ground and they will hold a fair amount of water even with the 38mm holes open.

I blasted mine with aqua-pure powder from the camping shop, the stuff that comes in little plastic tubs. I must have put about a mug of powder in each before filing.

While it was cleaning there was foam everywhere!

But after a soak of around 3 hours I then started rinsing through with the hose, giving the bag a good shake out, I would guess I rinsed about 3 times each, until the water stopped tasting.

That was last year and the year before for the other tank, they are still fresh on the boat. I did however change all the food pipes from tank to pumps.

I used the same principle as I do on my pool occasionally, it is called shocking it, ie. Having so much chlorine that you are sterilising rather than just keeping nasties at bay.

 

[milfordman]

I had one those flexible water tanks in my first cruiser which was a Sea Wych. Right from new I was advised to put a new penny in the tank, I was told that the small amount of copper leaching out would not be a health hazard but would keep the nasties at bay. Some people may say that was unhealth, however it worked, and I am steel here to tell the tale 30 years later. But then some smokers could say the same, but I would not advocate smoking.

 

[ShipsWoofy]

I have heard of that before, I think, or something similar, it rings a little bell in long term memory.

 

[jhughes]

And certainly no worse than all the copper and maybe even lead piping your tap water comes through!

 

[PeterGibbs]

If light gets at the tank it will encourage the growth of algae; the chlorine in normal water will not be enought to inhibit this. You will have to purge with proprietary cleaner, and probabaly scrub too to completely remove it.

All water tanks accumulate particles with time - deposits and condensates. Water supplied through marina hoses has its own additions. These will not normally affect the potability of the water. Using Milton or a PL version will keep tanks clean for potability purposes if used at the end and beginning of each season.

Avoid vinegar or other kitchen cupboard solutions - if you don't want to damage your system.

Final point: I cut into my water system some years ago and fitted a Whale filter, which lasts a season. The replacement filter costs about £19 a year, and excellent value it is too. So my galley cold tap tasts bewtiful, whatever happens in the water tank.

PWG