How long do Carbon Filters last?

[Scotty_Tradewind]

, you could always add a tablet or two when filling, The retail tablets available I find leave a horrible taste to the water.

Philip

Hi Philip,
apologies, omitted to say we do add tablets when filling and we do flush the tanks at beginning of season,
Agreed also that water can taste and smell if overdoing the pills.
If in the U.K. I have also left a small amount of water in the tanks with a small quantity of salt to flush through the pipes and taps to reduce risk of trapped water in pipes and pumps from freezing.
...................................................
We do live aboard for a few weeks on end in the summer and use the water for the odd shower, washing up etc. We've learnt to conserve tank water quite well .

Thread drift.........
'Crossing Biscay this summer'.
The crew, 4 of us in total, got through both tanks in two days on our trip down the south coast to Salcombe. After discussion was held, we managed to use half of one tank and very little of the other in our five and a half days from Salcombe direct to Baiona.

We also adopted a regime of having a 2 litre bottle of drinking water each with our names on, to ensure that we drank most of it each day. Surprising how little some people get round to drinking if not careful.

S.

 

[Hydrozoan]

I originally had a flexible tank, flexible hoses and carbon filters (which may also have incorporated silver for bacteriostatic reasons – I cannot recall). I changed them annually IIRC – I think the maker recommended that.

I changed to a stainless tank – because of tank leakage problems – and when I extended the system and fitted an electric pump and a hot water system, I re-plumbed with hard plastic and joints – again, not primarily for health or taste reasons - and decided to omit the filters. I use commercial disinfecting tablets when filling the tank - and clean the tank and pipework annually using a related disinfection product. I am careful to run marina water to clear the hoses before filling.

 

[Ian_Edwards]

Thanks, for everyone for replying, but no definitive answer to the question!

The application is not directly for drinking water, but to remove the Chlorine from the water, so that it can be used to flush the membrane in the reverse osmosis water maker, So the filters get very little use, perhaps 10L or so whenever I leave the boat for more than a few days. I guess not much more than 100L per year.
So I guess the question is not so much about whether the water tastes good, or is the carbon still active and able to remove Chlorine from the water, after it's been sitting there for a few month.

I'm also unsure whether UK mains water is still Chlorinated these days, there seems to be a lot of UV treatment around, but is this instead of Chlorine or in addition?

 

[Hydrozoan]

... I'm also unsure whether UK mains water is still Chlorinated these days, there seems to be a lot of UV treatment around, but is this instead of Chlorine or in addition?

Chlorine is the most commonly used disinfectant. (http://water.wuk1.emsystem.co.uk/ho...hnical-briefings/chlorine-policy-position.pdf)

I'm not a microbiologist, nor up to date with disinfection practices across the UK, but I do know that it is important to ensure that a disinfecting residual is maintained when the water is passing through the distribution system subsequent to treatment.

Thus section 7.1 of the DWI’s “Guidance on the use of Ultraviolet (UV) irradiation for the Disinfection of Public Water Supplies” (February 2010; http://www.dwi.gov.uk/stakeholders/guidance-and-codes-of-practice/uvirradiation.pdf) states that: “Disinfection is a process of water treatment to remove, or render harmless to human health, every pathogenic micro-organism and pathogenic parasite that would otherwise be present in the water. To manage risks in distribution systems once this has been accomplished, it is normal operational practice for water suppliers to maintain (or introduce and maintain) a concentration of residual disinfectant. For example, a supplier may introduce a residual level of free chlorine after UV irradiation.”

I don’t know how widely UV is used now, if UV alone is ever considered sufficient to maintain a residual, or if ozonation is used instead of chlorine after UV in some cases. If it is important to know the exact treatment sequence, a water user should contact their supplier.

I hope that helps.

 

[alant]

Would a PH pen tell you? They are as cheap as chips.

pH, is a measure of acidity (hydrogen ion content), whats that going to tell you about bugs/carbon filter?

 

[alant]

Thanks, for everyone for replying, but no definitive answer to the question!

The application is not directly for drinking water, but to remove the Chlorine from the water, so that it can be used to flush the membrane in the reverse osmosis water maker, So the filters get very little use, perhaps 10L or so whenever I leave the boat for more than a few days. I guess not much more than 100L per year.
So I guess the question is not so much about whether the water tastes good, or is the carbon still active and able to remove Chlorine from the water, after it's been sitting there for a few month.

I'm also unsure whether UK mains water is still Chlorinated these days, there seems to be a lot of UV treatment around, but is this instead of Chlorine or in addition?

Also added Fluoride.

 

[Hydrozoan]

Thanks, for everyone for replying, but no definitive answer to the question!

The application is not directly for drinking water, but to remove the Chlorine from the water, so that it can be used to flush the membrane in the reverse osmosis water maker, So the filters get very little use, perhaps 10L or so whenever I leave the boat for more than a few days. I guess not much more than 100L per year.
So I guess the question is not so much about whether the water tastes good, or is the carbon still active and able to remove Chlorine from the water, after it's been sitting there for a few month. ...

Well, with respect ) ) we now have a fuller question and more information - though we don’t know how big the filters are, for example. But even if we did, there are so many other factors (e.g. the chlorine content of the water – which may itself vary, the organic content of the water – which could affect the filters directly or through promoting bacterial growth, the chlorine level permitted in the flushing water) that I for one wouldn't hazard a guess.

I know nothing of RO water makers, but one thought does occur: if you know (or can get from the maker) the maximum tolerable chlorine concentration in the flushing water, you could explore whether or not a simple chlorine test kit (of which there are many, and not necessarily expensive in relation to RO membranes I should think) would have a sufficiently low limit of detection to allow you to test the water from time to time. That way you could in principle change the filters as and when you really need to.

Or am I barking (either up the wrong tree, or more generally )?

PS I don't think alant's fluoridation is relevant - the fluoride will probably pass through the filter, and its concentration will be low anyway).

 

[alant]

Well, with respect ) ) we now have a fuller question and more information - though we don’t know how big the filters are, for example. But even if we did, there are so many other factors (e.g. the chlorine content of the water – which may itself vary, the organic content of the water – which could affect the filters directly or through promoting bacterial growth, the chlorine level permitted in the flushing water) that I for one wouldn't hazard a guess.

I know nothing of RO water makers, but one thought does occur: if you know (or can get from the maker) the maximum tolerable chlorine concentration in the flushing water, you could explore whether or not a simple chlorine test kit (of which there are many, and not necessarily expensive in relation to RO membranes I should think) would have a sufficiently low limit of detection to allow you to test the water from time to time. That way you could in principle change the filters as and when you really need to.

Or am I barking (either up the wrong tree, or more generally )?

PS I don't think alant's fluoridation is relevant - the fluoride will probably pass through the filter, and its concentration will be low anyway).

If its RO, should already have a chloride test kit, to check for salt slippage.
Chlorine in drinking water is at (or should be) very low concentrations, so will a simple test be accurate enough?

 

[PatrickB02]

Apologies for the slight thread drift, but my boat has a couple of these filters:

They need to be replaced, but all of the online sources I can find seem to be charging about £20 per cartridge (even the caravan shops), which seems a bit steep to me.

Does anyone have a cheaper source, please..?

 

[Trundlebug]

Apologies for the slight thread drift, but my boat has a couple of these filters:

They need to be replaced, but all of the online sources I can find seem to be charging about £20 per cartridge (even the caravan shops), which seems a bit steep to me.

Does anyone have a cheaper source, please..?

Can't help with an alternative source I'm afraid, but by way of comparison the Jabsco carbon filter is around £40 IIRC, so maybe yours isn't so steep after all!

 

[johnalison]

Apologies for the slight thread drift, but my boat has a couple of these filters:
They need to be replaced, but all of the online sources I can find seem to be charging about £20 per cartridge (even the caravan shops), which seems a bit steep to me.

Does anyone have a cheaper source, please..?

We use Jabsco filters, which are presumably much the same. They cost around £25, so are not cheap, but worth it for improving the taste and saving on bottled water. On our last boat we had some in-line filters which used to discharge their granules into the system if I left them in for more than a year.

 

[Ian_Edwards]

Apologies for not putting enough info' in my initial post, I was expecting a general answer along the lines of, yes, it well known that they degrade after 6 months, as the supplier suggest, or, no they last a lot longer than that.

However, it seems a lot more complicated than that.

The membrane is a Dow Filmtec, the quote tolerance to Chlorine is <0.1ppm.
The carbon filter is a Wassermann MX1C (5 micron) Coconut Block 10" Cartridge.

The watermaker doesn't have any instrumentation to measure the salt content of the output, so getting something to test the drinking water is probably a good idea, so I'll do some research on that. It may help me determine when the filter needs changing and how "good" produced water is.

I do have a tap connected to the output of the watermaker where I can sample the water before it goes into the tank, I've never tasted salt in the drinking water, so I've assumed it's OK.

When I fill-up a marina I happen to visit, I've no idea for how the water is processed or what the Chlorine content might be, so testing it before I fill up is something I might try, if the test kit are relatively cheap and easy to use.

 

[Hydrozoan]

A very quick search suggests the following regarding test kits:

Swimming pool test kits (at ca. £15) seem to have 0.5mg/l as the lowest colour gradation, so that’s too high.

Some Lovibond and Hach systems go down to 0.02mg/l, but are £100+ (I think).

This Hach kit to 0.1mg/l is about £80 (http://uk.hach.com/chlorine-free-to...kit-model-cn-66-pk-100/product?id=24929260229), but that’s perhaps marginal in relation to the quoted tolerance (you’d need to look carefully at the details). And you might find something of similar LoD but cheaper.

It may be a non-starter on technical, practical or cost grounds, but I just offered the testing idea now that we have a clearer view of your concerns. And it would also depend on the cost of your filters, and how often you’d replace them with - or without - chlorine testing.

Anyway, good luck!

 

[JumbleDuck]

Apologies for the slight thread drift, but my boat has a couple of these filters:

They need to be replaced, but all of the online sources I can find seem to be charging about £20 per cartridge (even the caravan shops), which seems a bit steep to me.

Does anyone have a cheaper source, please..?

That's what I use; that's what I pay.

 

[NormanS]

We all seem to have become terribly precious about what's safe, and what's not. For generations the Clyde Cruising Club Sailing Directions would say, in relation to anchorages, "Water at burn". Very few died.

 

[smithy]

I fitted one of these, filters £5 on line
http://www.screwfix.com/p/high-capacity-water-filter-kit-10/16747

 

[Hydrozoan]

We all seem to have become terribly precious about what's safe, and what's not. For generations the Clyde Cruising Club Sailing Directions would say, in relation to anchorages, "Water at burn". Very few died.

Sure, and I spent many happy youthful years fishing in the Welsh mountains, drinking from streams and springs with no ill effect. But outbreaks of cryptosporidiosis in a water supply can have very serious consequences for the immunocompromised (e.g AIDs sufferers), cancer patients on chemotherapy, and very young and very old people. The risk is therefore treated very seriously by DWI and water suppliers – it may well have been to cryptosporidium (which is resistant to chlorine disinfection) that geem was referring at #11.

Happily, the OP’s issue with chlorine is a rather different one.

 

[alant]

We all seem to have become terribly precious about what's safe, and what's not. For generations the Clyde Cruising Club Sailing Directions would say, in relation to anchorages, "Water at burn". Very few died.

Wonder how many got liver fluke, from infected sheep discharge?

 

[ghostlymoron]

The fluoride is added where requested by the local health authority and has nothing to do with disinfection. In the UK , there will always be some residual chlorine in drinking water at the point of supply. So, provided the supply hose and the boats tankage and plumbing is clean, its quite safe to drink it. You should run water to waste from the supply hose before putting it in the storage tank. Buying bottled water or using clear bottles for drinking is unnecessary in my opinion.

Also added Fluoride.

 

[Alfie168]

It always amazes me that people are so paranoid about what they assume is clean water. The human nose and taste was developed to decide what was good or bad. If it's bad don't keep drinking it. If you get a upset stomach don't drink it.
Everybody seems to assume that water that come out of the tap at home is treated to oblivion. Most water companies don't treat their water for bugs. The recent episode in Lancashire took the installation of UV treatment to get rid of the bug. Lots of water that comes from reservoirs has little treatment. Fish poo in it. Stop being to clinical and stop worrying about a problem that doesn't exist. The body builds up immunity if you expose it. No exposure means no immunity.

Water treatment certainly does take place between reservoir and tap. How much depends on the source water quality, but what you can unequivocally say about all tap water supplied by water boards in the UK is that it has been chlorinated. Whether you can detect that varies on distance from the chlorination plant and the use or not of settling tanks which allow the chlorine to dissipate and turbidity (sand and grit) to settle. UV is only used in specific contamination cases such as the Lancashire one and only works properly on water with low turbidity levels. Aluminium sulphate is also used as a flocculating agent to clear water. The Camelford tragedy was an example of where use of aluminium sulphates went badly wrong.

As to the filter on boats. If its a small low cost filter I'd change it once a year at the beginning of the season after flushing the pipes with Milton or similar oxygenating disinfectant. Bacterial growth inside it and the pipes when unused is a definite risk, and you really do not want a bacterial gut infection. Some of them are very nasty and difficult to get rid of. A lot depends on how regularly the system is used as a system with regular use and fresh (probably chlorinated) water passing through it is a far safer bet than a system that has water sitting unused for months at a time.

I think the most important thing is to work out a regime of cleanliness that works for you, and stick to it. Most people on here seem to have one, and so what if they are all a bit different.

Tim