Do you carry Water Purification tablets ?

We dose the tank every time we fill up and have a cartridge filter under the galley sink to take the taste away so that it is fine for cold drinks, tea etc. Seems to be a good combination but is probably overkill as our boat is only 4.5 years old and filled from reasonable quality marina supplies in the UK.
 
Now this I am surprised at replies ... Until now I have never used tablets except when in UK to sterilise tank at start of season ---- or used Miltons.

It's only out here that I was worried about using my well water from the house - being untreated with chlorine based purifiers etc.

I never realised so many were using tabs on a regular basis. Made me feel happier about using them.

I also gather from the amounts people are putting in - they are not using 1 tab per litre as many instructions say ... but a greatly reduced dose. K..B with his 3 - 4 tabs per fill up is vastly less by sounds of it ...

Right that's sorted then - well water will get a dosing and a few sachets of tabs carried on board ...
 
Never use any tabs in my tanks, they are fibreglass and never stay full long enough to get stagnant! However I do have a biological filter in the sytem for all drinking, tea, icemaker and cooking water. (seperate tap) Once we are cruising again on watermaker water, will take once a day mineral/vitamin tabs.
 
I never used them in the UK except for a flush through after winter layup (1968 stainless steel tank), but out on the Chesapeake with the high temps and especially in some of the more rural marinas I do it for peace of mind.

Sounds like you're using very expensive ones designed for camping and back packing. The ones I use are specifically for boats. 1 tab treats 5 gallons, and are a fraction of the price of the type you seem to be talking about.

Even house tap water in Annapolis can have a bit of a sulphurous smell when you first turn the tap on, although I am assured it is safe to drink!! /forums/images/graemlins/shocked.gif
 
Well we drink our tank water all year round with no adverse effects, but then we do live aboard all year.

We treat our tanks about every 3 months or so with a dose of Milton as routine (125ml per 250 ltr tank), leave it stand for about an hour then use it as normal (500 ltr will last us up to 20 days at anchor with normal use). We will flush the tanks if we think they have got tainted taste then refill them and treat them with Milton again. The Milton tablets work fine but leave a taste for a good while longer than the liquid, but again it is fine for all uses including use as drinking water. We also pass the water through a Jabsco filter before it reaches any tap.

Porto Colom is the only place we have not taken water as was to heavily chorinated to use as drinking water, but everywhere else we've been the water on the quays has been fine. We have found that by using the water for everything the tanks stay clean and the water stays sweet as it is never standing long enough to be anything else.

The other advantage of drinking tank water is the extra storage as well as not having to transport loads of 5 litre bottles of water around - far better for the einvironment than bottled water and no plastic to get rid of in landfill sites.
 
Freestyle had a charcoal filter just upstream of a Whale hand pump for drinking water, but I had to remove it because it was on the negative pressure side of the electric pump and was letting air in.

The tanks are epoxy-treated ply, I think, which might have worried me if the boat wasn't 20 years old. Filling up with UK mains supplies gives them a periodic low dose of chlorine, but that doesn't last long. Once or twice a season, I pump the tanks "dry" and refill. I don't add anything else.

I'm happy to drink it, but the crew seem to prefer hot drinks or pickled water containing alcohol in variable amounts. The most unpleasant tastes seem to come from marina or yard supply lines, especially plastic hose left out in the sun (on which a film of algae can build up, and from which plasticisers seem to leach). Running the hose for five minutes is one option, if a little wasteful. Otherwise I use my own hose.

Can anyone think of any disease-producing germs that could have been present in, or contaminate a chlorinated public supply and breed in a dark water tank? Cryptosporidium is the only one I know that could survive such treatment, and is capable of surviving for months. Conventional water treatment procedures struggle to remove it, so UK water companies monitor their supplies like hawks now. If they find it, they have to inform the health protection authorities, who nowadays generally issue "boil water" notices. And cryptosporidium multiplies only in human and/or animal guts, so in the unlikely event that it is present in the mains water, you are no worse off drinking the stored water than the fresh.

If I had a problem with persistent taste, I would consider "hyperchlorinating" with Milton to achieve a final chlorine concentration of 5ppm or so, but I would flush it all out again after a few hours. Chlorine is corrosive to stainless steel, so don't overdo it.
 
[ QUOTE ]
....Sounds like you're using very expensive ones designed for camping and back packing. The ones I use are specifically for boats. 1 tab treats 5 gallons, and are a fraction of the price of the type you seem to be talking about.
......

[/ QUOTE ]

?? No it was a box of Nato issue tabs ... 960 of them for 13 quid. Water tabs

I looked at various other tabs and even made a spreadsheet to work out total cost per litre incl. p&p ... these came out at some incredibly low 0.016p per litre or something .... nearest competing was at 0.07p per litre ... and not in the quantity either.
My house well is 3m diameter and ranges in water depth from 1m to 4m depending on season. Today it's about 1.5m because of the hot weather. This is the period that water becomes murky - still safe but visually off.

This gives just over 10 cu.m of water = 10,000 ltrs. Mind starts to boggle !!
 
Aquatabs are the world’s no.1 water purification tablets. They are effervescent tablets which kill micro- organisms in water to prevent cholera, typhoid, dysentery and other water borne diseases. Aquatabs are available in a range of tablet sizes. Each tablet size is formulated to treat a specific volume of water – ranging from 1l to 2,500l.Aquatabs are used in emergency situations and also for continuous use in households that do not have access to safe drinking water.
It has many uses so therefore you can make used of it any where you go.
 
Just to add to the list - flexible tanks, hold about 100litres. Clean over the winter, fill and add 2 aquatabs. Thereafter, add another tab whenever topping up (usually 50l from containers, occasionally from a hose alongside) Only notice a slight chlorine smell when they first go in and never taste it.
 
We don't use any kind of purifying and we are quite happy to drink the water straight out of the grp tank moulded into the keel. We have never had any ill effects at all - if we did I would open up the tank and give it a clean out. The only water it has ever had in it during the last 14 years came from England, France or Guernsey - it doesn't seem to do the inhabitants of those places any harm - why should it hurt us?

When I was in the Merchant Navy I drank water from all over the world without ill effects. The only water I was ever told could be harmful, in the long term, was that produced in the ship's evaporator. I can't remember why that was -maybe it caused memory damage. :eek:
 
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Strange logic?

It always seems odd to me that some people are paranoid about using their tank water for drinking because it has been stood unused yet happily drink bottled water that has been sitting in plastic unrefrigerated for maybe more months.

We always used un-filtered water from out tanks, stainless ones on our last two boats over 23 years and it was fine. We cleaned the system on buying each boat (Puriclens powder added at double strength pumped to all corners and left for 24 hours before multiple flushing) but thereafter used nothing. The tanks were emptied over each winter but not treated again when refilled. We did use the boat every weekend and longer periods on board so had a high throughput and we always showered on board too, but then we also had large tanks with capacity (about 90 gallons) for the two of us for over 2 weeks continuous.

We were always careful on filling up to run the water for some time before adding it to our tanks, to get rid of any residual water in the marina pipework along the pontoons and we usually did this by filling after washing down the boat.

I might consider using tablets (plus a filter to take the taste away) in outer bongo bongo land however.
 
Moored up on the marina services pontoon overnight last night and judging from the number of people who tied up to fill their water tanks, shoving the water hose pipe straight into their tank before turning the water on, amazed me.

No idea how long the water had been stood in the hose before sticking it in their tank and I know from personal experience that the water in our marina hoses turns green within hours on a hot day.
So perhaps tanks should be dosed everytime.
 
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michael_w said:
The secret for keeping water sweet is to avoid light at all costs.
Click to expand...

Why do you say this?

My flexible tank is in a bladder; in a locker, with bunk cushions on top - absolutely dark, and it still goes mouldy after a few years - in spite of using aquatabs for every tank load of water.

No convinced that aquatabs stop mould growth, although it seems effective at stopping bacterial growth.

I also filter mine to get rid of residual taste.
 
Making water safe to drink means getting rid of bacteria, viruses and other pathogens (cryptosporidia etc). Oxidation kills the virus and bacteria, filtering removes most other pathogens. Oxidation is achieved by adding chlorine, iodine or silver to the water, and leaving it in solution for an hour or more. It is a pretty good bet to say that if you can very faintly smell iodine or chlorine, your water will be safe.

Unscented bleach (sodium hypochlorite in about a 5% - 6% solution) releases chlorine when added to water. Two drips per litre will do. Milton is sodium hypochlorite further diluted (less that 1% solution), so would require 10 to 20 drops per litre.

All sorts of "tabs" are iodine and/or silver salts in varying proportions, or maybe chlorine releasing compounds too. They all work by releasing free chlorine, iodine and silver ions. Generally, per litre, they are more expensive than "bleach", better suited to smaller quantities. With plenty of marketing hype to raise its value image.

If the chlorine or iodine smell is too offensive, add an acid. This forces the gas out of solution. Ascorbic acid (vitamin C) works, as does vinegar. Malt vinegar has its own offensive whiff, though! But once the smell of chlorine is completely un-detectable, you may no longer be protected against the possibility of bacterial growth - though the colony of nasties has first to be introduced. That's where the silver salts have an edge . . . longer term storage.

Of course, you could go for more colourful oxidants - potassium permanganate. Or other forms of bleach - hydrogen peroxide. But you then may be construed as a potential bomb maker or drug processor, so I'd play those cool.

Me? Good old bleach. An over-egged dose once a year through the whole system (taps on and all). Leave to soak for a day. Flush heavily, then flush with added vinegar to remove the chlorine stink. Empty and refill. Can I still just about smell chlorine? Good. That's it. If I can't, add one drip of bleach per litre and sniff again.

Easy, eh?
 
Nigel,
Perhaps your chemist has a product for sterilising babies' bottles like Milton here.
I dose my 15 gallon tank regularly and liberally ,but don't drink it , just washing up etc; my fresh water 2 gallon squashable portable containers get dosed with 2 tabs of Milton for the 15-20 minutes then filled with tap water, avoiding hot hoses. There's no taste and tea is fine,will last for at least a week ( if not sailing) without green algae tinting the plastic.

ianat182
 
ianabc said:
And the effect of chlorine on stainless steel water tanks is?
Click to expand...
Depends on the grade. Stainless 304 and 316 is routinely used in water treatment plants. 316 is preferred where chlorine levels are high.
The molybdenum-containing type 1.4401/4436 (316) grades, with their higher resistance to pitting and crevice corrosion, may be used for waters with chloride levels of up to 1000 ppm under the same conditions (at temperatures normally encountered in drinking water supply and treatment).
Click to expand...
That quote comes from the bible covering use of stainless steel in drinking water water treatment plants: http://www.euro-inox.org/pdf/map/GuidelinesDrinkingWater_EN.pdf
 
I have a couple of stainless tanks which I flush through a couple of times at the beginning of each season. I then fill the tanks using the required dose of Aquatabs. I always use them when refilling as well.

I use the aquatabs because the water is coming from a tap in the yard tap or from the end of a pontoon and you can't be positive it's not contaminated.

I then have two carbon filters in the galley and heads basin. I wouldn't be too bothered to drink the tank water, but as you can get 6 x 2l bottles of mineral water from Tesco for £1.20 I always use that for drinking/food preparation.
 
seagull water filter

ive fitted one of these to to the southerly ive just refitted, all i can say is absolutly brilliant the water now tastes better than spring water
 
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