Fresh Water Tank

muckypup

muckypup

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If a fresh water tank has not been used for several months, what do I need to do to make make the water drinking safe?

I'm assuming flush it through with some sort of steriliser?

Steve
 
I'm still pretty new to this boating lark but all the peeps I know with boats dont use the fresh water tank for drinking water. Yuck...even on my nice new S29 /forums/images/graemlins/laugh.gif
Always take containers of tap water from home and if away long enough to need more I find a decent tap and refill containers
 
Duno. Dog got sick with kidney trouble, then got diarea, we were on the boat at the time. Probably nothing to do with it, but I got a bit of belly trouble as well. So stuck some tablet thingies in, just to be on the safe side, not sure of the make.

We never had a bad taste though.
 
I've cut open filters I use on both my home supply and boat; found the same same gung I'm afraid. The water tastes fine. No chlorine.
Always use adequate protection that's what I say and don't use the same one twice!
JJTOP
 
Steve,

You need to flush entire water system through with either Puriclean or Chempro.
Puriclean available in a little tub at caravan shops, Chempro available at home brewing outlets, and some larger Morrisons.
Both are food grade sterilisers.

Fill the tank then add the powder, and draw through to all tap outlets...dont forget bathing platform shower if you have one.
This should kill all bacteria and algae in the system.

Leave it at least 24 hours and then drain off and flush through with fresh water.
To keep the water fresh add some Aquatabs or CleanTabs or similar, also available from caravan shops (about four tabs for a 75gallon tank) each time you fill tank.

As an aside, we only use the main tank water for washing etc, but even if only shaving in it, it can get in the mouth or any cut and cause the standard 2 day "camping tummy", which usually consists of sickness ,diorrhea and Colon cramps..not very pleasant. So even if using only for washing it needs treating.

We have a separate little 10 litre tank with a tap that we fill every day for our drinking water.

Steve
 
Put in just enough fresh water and Milton fluid at sterilising concentration (15ml per 2l water?) to sloosh over all surfaces at start of season. After slooshing, pump it out through all pipework, leaving just enough so when you top up with fresh water you end up with 2.5ml fluid per 5l water. Safe to drink at this concentration and no funny taste in tea/coffee. I normally don't bother to add any more Milton fluid during top ups for the rest of season and haven't had any probs.
 
[ QUOTE ]
Headmistress will jump in here with everything you ever wanted to know (cos I pm'd her! <G>)

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Yup...:)

Here's the method recommended in the US for both marine and RV fresh water systems:

Fresh water system problems--foul odor or taste--are typically caused by allowing water to stagnate in the system. Although most people think only in terms of the tank, the plumbing is actually the source of most foul water, because the molds, mildew, fungi and bacteria which cause it thrive in DAMP dark places, not under water.

There are all kinds of products sold that claim to keep onboard water fresh, but all that’s really necessary is an annual or in especially warm climates, semi-annual recommissioning of the entire system—tank and plumbing. The following recommendations conform to section 10.8 in the A-1 192 code covering electrical, plumbing, and heating of recreational vehicles. The solution is approved and recommended by competent health officials. It may be used in a new system a used one that has not been used for a period of time, or one that may have been contaminated.

Before beginning, turn off hot water heater at the breaker; do not turn it on again until the entire recommissioning is complete.

Icemakers should be left running to allow cleaning out of the water feed line; however the first two buckets of ice—the bucket generated during recommissioning and the first bucketful afterward--should be discarded.

1. Prepare a chlorine solution using one gallon of water and 1/2 cup (4 oz) Clorox or Purex household bleach (5% sodium Hypochlorite solution ). With tank empty, pour chlorine solution into tank. Use one gallon of solution for each 5 gallons of tank capacity. (There's a much easier way: use 1 liter/50 gal...mix with water before adding to the tank.)

To digress before proceding to step 2... Apparently unadulturated household bleach is not available in the Uk...it all seems to have fabric softners and God knows what other additives added (I find that hard to believe, but everyone insists its true). So here's how to arrive the right solution/dilution: In the US, Purex and Clorox household bleach is 7% sodium chloride in water. So find anything that's pure sodium chloride, create a solution that's 7% in water...and proceed...

2. Complete filling of tank with fresh water. Open each faucet and drain cock until air has been released and the entire system is filled. Turn off all the faucets, but do not turn off the pump; it must remain on to keep the system pressurized and the solution in the lines.

3. Allow to stand for at least three hours, but no longer than 24 hours.

4 Drain through every faucet on the boat (and if you haven't done this in a while, it's a good idea to remove any diffusion screens from the faucets, because what's likely to come out will clog them). Fill the tank again with fresh water only, drain again through every faucet on the boat.

5. To remove excess chlorine taste or odor which might remain, prepare a solution of one quart white vinegar to five gallons water and allow this solution to agitate in tank for several days by vehicle motion.

6. Drain tank again through every faucet, and flush the lines again by fill the tank 1/4-1/2 full and again flushing with potable water.


An annual or semi-annual recommissioning according to the above directions is all that should be necessary to keep your water tasting and smelling as good as anything that comes out of any faucet on land. If you need to improve on that, install a water filter. Just remember that a filter is not a substitute for cleaning out the system, and that filters require regular inspection and cleaning or replacement.

To keep the water system cleaner longer, use your fresh water...keep water flowing through system. The molds, fungi, and bacteria only start to grow in hoses that aren't being used. Before filling the tank each time, always let the dock water run for at least 15 minutes first...the same critters that like the lines on your boat LOVE the dock supply line and your hose that sit in the warm sun, and you certainly don't want to transfer water that's been sitting in the dock supply line to your boat's system. So let the water run long enough to flush out all the water that's been standing in them so that what goes into your boat is coming straight from the water main.

Finally, while the molds, fungi and bacteria in onboard water systems here in the US may not be pleasant, we're dealing only with aesthetics...water purity isn't an issue here--or in most developed nations...the water supply has already been purified (unless you're using well-water). However, when cruising out of the country, it's a good idea to know what you're putting in your tanks...and if you're in any doubt, boil all water that's to be drunk or used to wash dishes, and/or treat each tankful to purify. It's even more important in these areas to let the water run before putting it in the tank, because any harmful bacteria will REALLY proliferate in water hoses left sitting on the dock.
 
>>Apparently unadulturated household bleach is not available in the Uk<<
It is, but rare outside Miltons. I'll start looking for bleaches without surfactants, whiteners etc etc, though I suspect it will be a long search. Some of the US companies who own some of the UK supermarkets may be a good starting point.
 
No...as long as it doesn't remain in the tank for more than 24 hours and is very thoroughly flushed it, it will do no harm to a metal tank. Far less harm, in fact, than adding a just a fraction as much chlorine "purifier" to each fill.
 
So it looks the the bottom line here is be to clean & sterile. A good flush of the fresh water tank and sterilise regular. Add in tablets to keep water sterile.

I think if the above is done, then the water should be ok for tea/coffee if boiled? Probably take in a couple of bottles of mineral water for straight drinking as SWMBO is picky (and plenty of beer of course - for the *end* of the days sailing).

Steve
 
Look at Tesco Value brand bleach...

Tesco's own-brand "Value" thin bleach is only about 10p for a 2-litre bottle, so I assume it doesn't have any additives (and it doesn't list any in the ingredients info). I've used it in a water tank, with no dire consequences.
 
Thanks Peggy!
I will give it a try at the start of the season next year as during the past season a rotten egg smell developed in the water from the tap. However, I think it is not the tank but the hoeses as the smell goes away after running the tap for a few minutes. Maybe I could just fill the plumbing by feeding the solution straight into the pump?
 
The freshwater from my tanks is better than you can buy form the supermarkets - no aftertaste and a great additive to the amber nectar.

At the start of the season, I use puriclean in the tank for 24 hrs, making sure that the water has been pumped through all the pipes as well and tanks are full - preferably going out for the day so that the motion can agitate the water and really get to all the surfaces. I pump out and flush, and then add a single aquatab per 20 gallons. For the ultimate drinking water, I also have a jabsco aquafilter on the cold water supply.
 
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