water tank painting

[John Orentas]

I think people get excessively nervous about water tanks, I think if we were shown some of the storage and pipelines of the water companies we would never touch water again, (I avoid it after 9.00 pm)..

 

I think too that our sniffing and tasting tackle is quite good, in general if it smells and tastes OK it probably is.

[blackrose]

I think people get excessively nervous about water tanks, I think if we were shown some of the storage and pipelines of the water companies we would never touch water again, (I avoid it after 9.00 pm)..

 

I think too that our sniffing and tasting tackle is quite good, in general if it smells and tastes OK it probably is.

 

It's not just the quality of the water that's the issue. We paint the outside of our hulls to prevent corrosion so surely it's just as important to paint that part of the inside of the hull which contains water.

 

I'm in a similar position - actually the water tank was nicely blacked when we got our boat but we had some welding done on the side and where the weld line is it seems to have caused rust to come through on the inside of the water tank. Not quite sure why that would be?

 

Anyway - I want to avoid drinking water out of it as it never tasted too good (definitely don't drink out of it now - it tastes awful) so I was thinking of just adding a nice square stainless steel water tank which could go below below the well deck. The existing space is right in the very front of the bow so there is a large space below the well deck that can be accessed from inside the boat. So I need to know where I can get a stainless steel food grade water tank from - anyone know? I would just ask my local chandlers but not sure I'm going to get the best deal that way. Thanks.

 

Why not just T-off the cold water pipe on your kitchen sink tap and have a dedicated filter and tap for your drinking water? This won't be as expensive as fitting a new stainless steel tank.

 

http://www.generalecologyeurope.com/]

 

I bought the Nature Pure model at the London Boat show for £170 including a spare cartridge & everything needed to fit it.

Edited June 5, 2008 by blackrose

[benjamino]

Why not just T-off the cold water pipe on your kitchen sink tap and have a dedicated filter and tap for your drinking water? This won't be as expensive as fitting a new stainless steel tank.

 

http://www.generalecologyeurope.com/]

 

I bought the Nature Pure model at the London Boat show for £170 including a spare cartridge & everything needed to fit it.

 

Yeah might well go down that route. Still need to get my head round getting the tank and scraping and painting though, ugh. What should I paint it with? Is there anywhere online I can buy suitable stuff? Presumably its not just your standard bitumen?

[blackrose]

Yeah might well go down that route. Still need to get my head round getting the tank and scraping and painting though, ugh. What should I paint it with? Is there anywhere online I can buy suitable stuff? Presumably its not just your standard bitumen?

 

Standard bitumen will be fine unless you want to pay more for the same stuff in a tin which says "water potable" or something to that effect. Essentially it's the same stuff but the distributors of the latter have paid for tests to allow them to market it as such, and they need to recoup their money.

Edited June 5, 2008 by blackrose

[John Orentas]

Yeah might well go down that route. Still need to get my head round getting the tank and scraping and painting though, ugh. What should I paint it with? Is there anywhere online I can buy suitable stuff? Presumably its not just your standard bitumen?

 

 

B & Q sell a bitumen paint that is 'Suitable for water tanks'.

[alan_fincher]

We recently completely cleaned and de-rusted our integral water tank, and repainted it with two coats of the potable blacking intended for the purpose.

 

On first filling the water, there was a slight taste, but despite the tank not being fully emptied before the next refilling, after that the taste was only just perceptible if the water was drunk "pure", and not noticeable at all in tea or coffee. I think one more refilling, and there will be no residual "flavouring" at all.

 

People say you can save money by using normal hull blacking, but even at swindlers prices my special stuff only cost £6-95. It's hard to see how I could have bought a suitable quantity of hull blacking for less.

 

However if you do decide to go the stainless steel route, there have been several threads suggesting manufacturers. One was quite recent, so try searching.

 

A couple of thoughts....

 

1) Any stainless steel tank, however carefully designed and manufactured, will have significantly less capacity than the space into which you are trying to fit it.

2) A non integral tank will get condensation on the outside, so you at least need to consider whether to insulate or not, and that some water will probably drip down onto the base-plate.

 

Of course another option is one of those flexible "bag" type liners introduced into your current tank. I'd still want to treat and black the tank first though, as protection against any water, (condensation or otherwise) that found it's way between bag and shell.

[benjamino]

Of course another option is one of those flexible "bag" type liners introduced into your current tank. I'd still want to treat and black the tank first though, as protection against any water, (condensation or otherwise) that found it's way between bag and shell.

 

Yeah I'd heard about those - there's also a lot of info floating about about estrogen mimics and carcinogens associated with water contained in plastic so I'm wary of that for a long term solution. Of course bitumen may well have its uncertainties but as it's not used in any mainstream commercial food containers (as far as I know?) I doubt anyone has done any research into it.

 

Still, think I'll probably head to B+Q and get some stuff from there and do it. I noticed earlier in this thread people were talking about rust proofing products to treat the rusted areas after scraping/brushing - are these necessary to prevent the rust coming back? If so any further thoughts on what to use?

[alan_fincher]

Personally I went with two full coats of Vactan rust converter over the entire tank.

 

There wasn't a lot of rust after I'd cleaned it, but I reasoned I'd take no chances of leaving any in.

 

Then 2 coats of potable blacking, as bought from a chandlery. (Ive no idea if you can find equivalent in a DIY superstore or not).

 

Some people have gone with just the Vactan, and seemed to get away with it, reporting good water several years on.

 

I don't know which will be longer lasting - Vactan alone, or Vactan then followed by potable water tank blacking.

[blackrose]

From which perveyor does one procure Vactan? I think I need a few gallons of the stuff for my boat.

[alan_fincher]

From which perveyor does one procure Vactan? I think I need a few gallons of the stuff for my boat.

Postally from Paco systems.

 

http://www.paco-systems.co.uk/vactan.html

 

I'm not sure if there are alternate ways, but don't think many chandleries will carry it.

 

Do you mean gallons ?

 

A little goes a very long way. I know you have a big boat, but that will allow you to treat quite a lot of it.

[Mike Poole]

Personally I went with two full coats of Vactan rust converter over the entire tank.

 

There wasn't a lot of rust after I'd cleaned it, but I reasoned I'd take no chances of leaving any in.

 

Then 2 coats of potable blacking, as bought from a chandlery. (Ive no idea if you can find equivalent in a DIY superstore or not).

 

Some people have gone with just the Vactan, and seemed to get away with it, reporting good water several years on.

 

I don't know which will be longer lasting - Vactan alone, or Vactan then followed by potable water tank blacking.

 

 

Hi Alan,

 

Since you have an Evans boat as well was your integral tank completely sealed? Ours has no access at all although you can see a square of welded-down steel in the well deck which I suppose could be cut out again if necessary.

 

When we bought the boat we had thick brown water come through the the taps but after flushing and sterilising a few times we've had no problems since. I presume that some rust had developed while in brokerage what with the tank being part empty.

 

I suppose you have to do something about it sooner or later but I would have thought that the bulk of it would be off the top of the water tank on the underside of the well deck. Did you have a lot of rust rust all over the inside?

 

On the other hand I suppose a decade or so may be stretching it a bit. I'm just loathe to do anything about it just yet...

[alan_fincher]

Mike,

 

Our Evans & Son has access to the integral water tank via a removable steel plate in the front well deck.

 

Probably around 2 feet square, and simply sitting over a hole in the steel below that is about 1" smaller all round.

 

(So the hatch sits proud of the remainder of the well deck by the 6mm thickness of the steel).

 

Ours was fixed with (I think) 6mm brass countersunk bolts, which I have replaced with stainless steel.

 

There was a reasonable amount of rusting throughout our tank, despite having paid a professional to do it a couple of years previously. (It's difficult to check whether a proper job is being done in such cases, but clearly a case where I wasted my money).

 

I doubt Evans & Son would have made the hatch welded in, or they might just as well have never included it in the first place, (unless it was needed as part of the way the boat is built..)

 

It sounds more like a subsequent modification - is there any evidence of welded up bolt holes ?

 

Are you sure it's an integral tank, and that there isn't some kind of separate tank hidden away in there ?

 

Finally, I'm sure you told me once, but what year is your Evans, please ?

 

Alan

[MikeV]

I bought the Nature Pure model at the London Boat show for £170 including a spare cartridge & everything needed to fit it.

I fitted a second water filter and dedicated drinking water tap recently, mostly because SWIMBO noticed little black bit in the water. Actually I think these were just small bits of carbon from the relatively new filter in the Jabsco Aqua Filter which is in line with the main kitchen tap. Jabasco however don't make any specific claims for their carbon granule filter other than it "cleanses and freshens water".

 

In general, I think that so long as you are changing the water in the tank fairly frequently, you should not have any problems with drinking tank water even without a filter, although this was also at the time they had the outbreak of Cryptosporidium in mains water in the Northampton area where we were moored at the time so we weren't able to fill the tank.

 

I looked at the General Ecology Nature Pure filter and it is an excellent product, but quite expensive both initially and for replacement cartridges. I opted instead for a standard 10 inch domestic filter housing which I was able to fit in dead space within the corner cupboard. There are loads of manufacturers of standard 10 inch cartridges and many different types of filter medium depending on what you want to remove from your water. I bought some 0.5 micron carbon block filter cartridges which claim to remove or reduce many things, including bacteria such as Cryptosporidium, Giardia, Entamoeba & Toxoplasma. Total cost of filter housing, tap and cartridge was about £30 (all bought on eBay).

[Mike Poole]

Mike,

 

Our Evans & Son has access to the integral water tank via a removable steel plate in the front well deck.

 

Probably around 2 feet square, and simply sitting over a hole in the steel below that is about 1" smaller all round.

 

(So the hatch sits proud of the remainder of the well deck by the 6mm thickness of the steel).

 

Ours was fixed with (I think) 6mm brass countersunk bolts, which I have replaced with stainless steel.

 

There was a reasonable amount of rusting throughout our tank, despite having paid a professional to do it a couple of years previously. (It's difficult to check whether a proper job is being done in such cases, but clearly a case where I wasted my money).

 

I doubt Evans & Son would have made the hatch welded in, or they might just as well have never included it in the first place, (unless it was needed as part of the way the boat is built..)

 

It sounds more like a subsequent modification - is there any evidence of welded up bolt holes ?

 

Are you sure it's an integral tank, and that there isn't some kind of separate tank hidden away in there ?

 

Finally, I'm sure you told me once, but what year is your Evans, please ?

 

Alan

 

Thanks Alan,

 

The boat is either '97 or '98 depending on which bit of paper you look at. I think maybe the shell was bought in '97 and the boat registered in '98 after fitting-out.

 

I suppose the hatch thing must be something the original owner did. Mind you it's not very big. I suppose they could have blacked it and welded the plate on. There are no old bolt holes and in the 'ole under the front steps the stop tap is connected directly to the front of the steel mini-bulkhead which also has insulation round it (Although I suppose it would be connected there anyway!). There are no other entry points hidden away behind there that I can find. Judging by how long a full tank lasts (nearly a week with showers, washing machine etc.) I don't think there's a smaller tank hidden away. I'll have another look though at the weekend (when I take out all the power tools, spare hoses and hopefully some cans of beer I mislaid.

 

On a slighlty different tack, can you see the engine number on your BMC? I can't find one anywhere on mine. It looks like a Gold Seal refurbished one but the gold paint is no guarantee I suppose. It's just that the settings for the tappets differ depending on the age. The older ones are 17 thou and the newer 14 I think. The book I've got gives a range of engine numbers for each one. (I suppose it could be Turkish even. Can you distinguish them easily?)

 

Cheers,

Mike

[alan_fincher]

OK, Mike,

 

Understood about the tank.

 

Strange to have an integral tank you can't get in to - I don't think I'd be too keen!

 

I've PMed you about engine identification, as it's off topic.

 

Alan