Water tank sterilising??

[jimbo]

Just wondered what you guys would recommend as a good product for sterilising my water tanks on the boat. According to the Bounty Boats brochure I think the capacity is 140 gallons so will probably need quite a bit of the stuff!!!

[SteveO]

We have never bothered to sterilise our water tank and have not come to any harm. I think that, providing the tank is clean and made of inert material, the residual chlorine in the mains water you use to fill the tank should be sufficient. If you need more than that, there are proprietary sterilising tablets you can buy from chandlers or you could try boosting the chlorine with something like Milton sterilising fluid added to the tank before you fill up with water, then dump the contents and refill and you should be OK.

Regards

Steve

[jillR]

hi steve

not sure about the milton

my memories of it are that its not usable with metal

jill

[Guest]

Hi Jimbo,

My water tank is also 140 litres - but I find that with normal usage, we get through it fairly rapidly anyway, and are always refilling, so I don't bother with any sterilising. Just continued, regular use, will ensure you are always using fresh water, not stagnant stuff, and as Steve says, the normal chlorine in the tap water we fill up with, should be sufficient to kill off anything in your tank.

Unless folk go down with terrible stomachs after using the water, I would guess that there is little likelihood of anything undesirable lurking in your tank, that your normal immune system wouldn't be able to deal with. I think we can sometimes get a bit too sensitive about wanting to sterilise things that have never really harmed people.

[Antares_9]

In days of yore when water quality was poor, people used to use it in cooking and boil for tea and other infusions. For drinking they had beer, I find this still works well today.

Seriously though, you are unlikely to come to harm if you circulate the tank regularly, for good measure, as has already been said, you can use the proprietary tablets which is what I do. However if what you want is better tasting drinking water and the added biological filtration I suggest one of the silver based filters like aqua pure changed once a season which again is what I use.

[jimbo]

Thanks for the replies folks, I take your point about the chlorine doing it's job, but the reason I have decided to sterilise the tank and pipework this season is because I am only able to get down to the boat once a month.

On returning to the boat, when I run one of the taps I get a really eggy horrible smell for a while untill plenty of water has run through the tap

This is the reason I think the whole system would benifit for a good sterilising??

[jimbo]

Thanks for that Rod, I suspected this was a job I should really be doing. The tanks on my boat hold 140 Gallons I think so im going to need quite a bit of the stuff!

I have found a chap on ebay selling Milton by 2x 5 litres but Jill seems to think you cannot use it with metal tanks???

[SteveO]

Jimbo, what is your water tank made from?

The bit about the eggy smell worries me and I have to say that, if I had this, I would be thinking about cleaning and disinfecting the water system. The smell is most probably hydrogen sulphide produced by bacteria. I don't think it is harmful, but the human nose is quite sensitive to it and can detect it down to 1-2 ppm.

If the tank is stainless steel, then you should be OK with Milton, which is a mixture of sodium hypochlorite (bleach) and sodium chloride (salt), but don't leave it in too long, or a proprietary tank cleaning agent. Either way I would be inclined to drain down and re-fill with fresh water afterwards because chlorine tastes horrible. If the tank is galvanised, it is possible that the galvanising has broken down and you would do well to find out what is inside it, via an inspection hatch if it has one. There may well be a layer of rusty sediment and/or slime on the bottom of the tank, which can give rise to the rotten egg smell. If this is the case, you might want to remove this (often easier said than done). The reason is that sediments and slimes will protect the bugs in the tank from the cleaning solution.

Also, if you are planning to use a carbon filter in the water system, you should check with the supplier whether this can be left in place whilst flushing the outlets with sterilising solution.

Regards

Steve

[jimbo]

Hi Steve,

The tanks are made of stainless steel, I suspect that the bacteria builds up in the pipework where the water is just sat there, as the smell clears when you run a good ammount of water through it.

The whole system is drained down at the moment so I will give it a right good cleaning through at the start of the new season.

How much Milton do you think I will need to blitz 140 gallons ???

[kfurbank]

Hi Jimbo,

Best stuff to use is Aqua Tabs from any chandlers or Camping stores. They come in two different sizes. Normal and mega tab. I bought a pack of the mega tabs and added just one to the tank and could smell the chlorine for a couple of fills. The normal tabs I just add to the tank about once every five or so fills and don't normally get too strong a smell from them. The tablets are meant to sterilise the water and make it safe for drinking as well, although I still prefer to use bottled water for drinking, but for showering, washing up and brushing teeth etc, then the aqua tabs are fine.

Another alternative I have thought about, but not got round to trying, is to speak to your local friendly publican and get some off the stuff they use to sterilise the beer lines. It does the trick for beer lines ans must have to meet a fairly high standard.

Keith

[Mowjo]

Jimbo! are your water pipes the clear braided ones by any chance?? because I had the same problem with my Freeman, since I changed them to the Blue water pipe I've not had any problems with first run smell! someone told me something like, because the pipe was clear the light encourages stuff to grow in the pipe, I cleaned a short bit of the pipe out with rag and it came out green and slimmey, also I got my Blue water pipe from our caravan shop at Yarmouth, it was half the price of the same stuff from the Chandlers,

Frank,,,

[jimbo]

Hi Keith and Frank,

Keith I will look out for some of those as they sound ideal! I also thought about the beer line stuff just to do the pipework with but I think it is Caustic Soda they use which is probably a little too savage

Frank My water piping was all renewed just before I bought the boat, it is the blue pipe you describe. I have also heard the clear pipe and light theory which makes alot of sense when you think about it

[kfurbank]

Jimbo,

I have found some normal Aqua tabs here

http://cgi.ebay.co.uk/Aqua-Tabs-Aquatab ... 240%3A1318

they say they treat about 5 gallons per tab, which at that price isn't too bad, although I would never put in that many unless you like the taste and smell of chlorine. If you can find the megatabs anywhere then they are probably best for your first treatment and then just chuck a few of the normal ones in every now and then. From memory I got the mega tabs from Norfolk Marine Wroxham.

Keith

[jimbo]

Thanks for that Keith, I will be down there this week so will pop in and see if they have any Must remember to take just enough money to buy them and nothing else

[jimbo]

http://www.marinescene.co.uk/product/48 ... -mega-tabs

The Mega tabs look better value Keith with each tablet treating 50 Gallons I recon 3 of those dropped in now and again will sort the job out

Thanks again.

[SteveO]

The tabs are a good idea Jimbo. Mowjo makes a good point about the pipework. If there is any slime in there, the chlorine in the tablets won't kill the bugs that cause the smell.

Good luck!

Regards

Steve

[kfurbank]

Hi Jimbo,

That's the ones. You might find three does the trick for the first application, but I would seriousely consider the normal size ones for a regular application. Three mega tabs as a normal application and you will smell like you have just come out of the swimming pool each time you have a shower. They are seriousely effective though.

Keith

[boycee]

Hi people

Just picked up this thread-Used to steralise my water tank with Tabs but around 5 years ago had an in-line filter fitted to the cold water system prior to it reaching any Taps-Providing it is changed every couple of years I have to say it has been a big success & is a lot easier to manage.However SWMBO insists that water from the cold taps should not be used for drinking purposes on Sandpiper, hence we always have a couple of large Spring Water Bottles on board.We do however use it when we brush our teeth, but otherwise boil it first for Hot Drinks etc & we have had no problems to date-touch wood.I believe these filters are obtainable from most boat chandlers and are relatively easy to fit,although being a lazy guy, the Boatyard fitted mine

Boycee

[TeamElla]

Can I add something to this debate.

All the above relates to water already in the tank but we have found a need to control what's being introduced in the first place:-

Like any other marina based boaters, we fill the fresh water tank at the berth before leaving the marina. We also buy 5 litre bottles of spring water just for drinking. It wasn't until I decided to fill an empty 5 litre bottle from the marina supply that I found just how much muck I was putting into the tank to start with.

Our fresh water pipes are flexible for their entire run along the pontoons and they build up a deposit of "algae" on the pipe inside walls during the warm months which eventually breaks off and gets invisibly delivered into our tank.

I noticed this when I filled a bottle from the marina tap and it was absolutely full of black particles up to 10 mm long.

Last summer I had a full bottle of spring water and a full bottle of the clearest fresh water that I could obtain from the marina tap in the wheelhouse. They ended up staying there for a month, at the end of which the spring water was crystal clear and the other was decidedly green.

There's not a lot that we can do about this other than to use a funnel with a fine mesh filter when filling the tank. It's quite an eye opener just how much "flotsome" would have been introduced otherwise (providing a build up of debris and possible breeding ground for some of the bugs that have been mentioned).

Steve