Fresh Water Tank smelling/foul tasting

[Sinbad1]

Tank is 300 gallons so lots of flushing is not easy. What actually causes the smell/taste and what is the simplest way to remove and prevent it happening again.

The tank is rubber lined so has no means of access, thus I require something that can be added externally via the inlet pipe.

Thanks all.

 

[charles_reed]

It's probably an anaerobic bacteria producing H2S which, once you're infected, is very difficult to remove.
To get rid of it use an ordinary oxidising agent such as sodium hypochlorite or potassium permanganate - the latter is less effective but the aftertaste less difficult to get rid of.

To prevent re-infection ensure there is no hint of light getting into pipework (where you usually find the locus of infection) or tank.

It's usually fairly easy to get out of the system (the good news) but the sftertaste of the treatment needs between 3-5 flushes (the bad news).

Good luck

 

[steve_cronin]

I've never owned a boat that we haven't used hypo water purifying tablets with. The flexibles on our last boat were particularly prone to sliming and therefore bad tasting. A good winter cleaning regeime is vital particularly with neoprene liners. A good strong solution of Puritabs or Aquatabs in hot water poured in and left for an hour or two before pumping out and flushing through several times with clean water will do the trick. Then always use one tablet per 5galls capacity every time you re-fill. If you don't like the slight chlorine taste - boils off in hot drinks - use spring water for your scotch & the kids' squashes - fit an animal charcoal/silver filter in line to the galley pump.

Steve Cronin

 

[JeremyF]

A bottle of Milton Fluid usually does the job. Leave it in for 24 hrs, and flush through 3 times. Let the pump rest after every 10 mins, as they can burn out quite easily.

Jeremy Flynn
Dawn Chorus

 

[ccscott49]

I use the puritabs powder stuff and pump it through all the lines and leave for a day, then pump it out through all the taps and flush three times, this does the job for me. I also have one of those general ecology charcoal/silver filters, (which are excellent) with a seperate tap, which gets used for all drinking purposes, cooking I use normal tap, as it's going to be bolied. I know it's a pain, flushing all that, expensive in the meddy, water through, but I'm afraid it's neccessary.

 

[PeterGibbs]

From 4 year's of battling this problem, now solved, I suggest:

1. Use Milton in the tank over the winter. Flush out well. In the season keep the water flowing, top up regularly - still water absorbs nuisances!

2. Install a filter - I use a Whale in line type - to the drinking tap (galley) This works a treat - good enough to use for making tea, and that IS a test!.

Peter Gibbs

 

[Steve_Harrison]

It smells because of stagnation and could be caused by the bacteria cryptosporidium. I've found that a large single dose of Milton left for 24 hours does the trick. If your tank is rubber lined though and not poly lined, be careful not to leave any treatment in for too long 'cause it has a degrading effect on some materials.
Steve.

 

[VMALLOWS]

I can also recommend CHEMPRO SDP which is a standard 'Home Brewers' product widely available in such outlets (usually heath-food shops these days). Look for the big 500g pack which makes 100 gals of full strength solotion for £3.99, though it will work fine at quarter strength if left in for about 12 hours.

As a proprietary product, they dont list the ingredients, but it is essentially an oxidising agent similar to 'Steradent'. Its amazing the 'dirt' it will shift. Needs 2 (min) flushes. I have never detected any 'after-taste' ...except that the water tastes better than before! Of course my main use is for brewing/wine-making!

 

[chippie]

I was going to suggest the same thing,I know it as metabisulphide.

 

[VMALLOWS]

Sodium Metabisulphate (preferably with a little acid such as citric) is an excellent contact steriliser but it is completely different from CHEMPRO. It does not 'lift' adhering stains/deposits into suspension to anything like the same extent.

In home brewing I use Metabisulphate as my basic steriliser for bottles etc between brews, but after a time (say every 5 brews or so) I use CHEMPRO to give the bottles a thorough clean: it's amazing how much residue comes off and how clean the bottles are afterward. Unlike Metabisulphate (which I simply pour from bottle to bottle and drain out before re-filling the bottles), CHEMPRO does need to stand for about 30 minutes and then be rinsed out a couple of times with fresh water, so it's a bit more tedious to use.

 

[VMALLOWS]

Before I get jumped on by the chemists out there, I did of course mean Sodium Metabisulph*ITE* (not *ATE*).

 

[ccscott49]

I'll try and get some of this stuff, for my anual cleanup this year, I can leave it in there for a few days, in fibreglass tanks, would that be OK, do you think? I would flush the tanks through about three times as usual.

 

[Boathook]

It could be worth stripping out the inlet and outlet hose to make sure that they are clean etc. Also a little used pipe to a water heater or similar could be causing the problem. I know that it is on my boat & it's a winter project to strip and clean pipes and fittings.

 

[VMALLOWS]

Yes, you can leave it in for a few days and it won't do any harm. However, ideally, I'd suggest about 3-4 hours so that the 'dirt' is still in suspension and most is removed on the first pump-out. If you leave it longer, the 'dirt' will settle to the bottom and will have to be stired up again during the flushing to remove it.

As Peter says, be sure to treat the hoses which are normally empty (eg the inlet pipe). This can be difficult because water leaks out of the taps etc and it is not possible to keep the pipe(s) full for long enough.

 

[oldsaltoz]

G’day Stuart,
Take a look at the link below, should provide you with the answers you seek.

www.boatered.com/pres/phmenu.htm

Soavagoodweekend Old Salt Oz……

 

[oldsaltoz]

G’day Stuart,
Take a look at the link below, should provide you with the answers you seek.

http://www.boatered.com/pres/phmenu.htm

Soavagoodweekend Old Salt Oz……

 

[ccscott49]

I'll remember that, thank you, my inlet pipe will stay full for an hour or two, so it should be ok, I'll get some of this stuff when I visit UK, later in the year. Thanks again for the advice.

 

[Sinbad1]

Thanks everyone who responded. Will try the chempro route first.

Sinbad