Water filtration w/ no pressure pump

[Target9000]

Quick question for you plumbing gurus...

Do the marine/RV water filtration systems work well in a fresh water system that uses only manual pumps instead of an electrical pump? I had read somewhere (though I can't find it now) of one guy's troubles manually pumping through a filter.

[a64pilot]

If you lower the flow rate through a filter, it's likely to serve it's filtering function even better, but any filter will have some restriction so it will require more effort to pump through, shouldn't be too bad, we are talking about filtering just for cooking and drinking, not bathing or something right?
Of course you want to put the filter on the pressure side of the pump, not the suck side.

[Target9000]

Originally Posted by a64pilot

If you lower the flow rate through a filter, it's likely to serve it's filtering function even better, but any filter will have some restriction so it will require more effort to pump through, shouldn't be too bad, we are talking about filtering just for cooking and drinking, not bathing or something right?
Of course you want to put the filter on the pressure side of the pump, not the suck side.

That is right, just for drinking and cooking. We have a MK4 tiptoe pump in the galley. I hope it has enough "umph" to push the water through a good filter. I was thinking of putting a seagull in or something of that sort.

[model 10]

A regular under sink filter causes no problems with a foot pump. If you get generic housing you will be able to get filter elements almost everywhere in the Americas. Sometimes they are a bit long so you need to smack them on the floor to make them just a bit shorter. I would hesitate to buy something fancy made just for a boat. You don't need more problems finding parts. A clear housing is a plus as you can see how gross the element is. In the US you can buy hard carbon/ ceramic elements ($40!) and they really make your water taste good.

[Arthur Garfield]

Hi Guy,
Go these filters you write of desalinate or just larger particles?

[Target9000]

Originally Posted by Arthur Garfield

Hi Guy,
Go these filters you write of desalinate or just larger particles?

They just filter larger particles. Desalination is a whole other world and requires lots of power and pressure, beyond the scope of this discussion.

[thinwater]

Originally Posted by Guy

A regular under sink filter causes no problems with a foot pump. If you get generic housing you will be able to get filter elements almost everywhere in the Americas. Sometimes they are a bit long so you need to smack them on the floor to make them just a bit shorter. I would hesitate to buy something fancy made just for a boat. You don't need more problems finding parts. A clear housing is a plus as you can see how gross the element is. In the US you can buy hard carbon/ ceramic elements ($40!) and they really make your water taste good.

Please clarify. Have you used a carbon block or ceramic filter NSF 53 rated to remove cysts (~ 0.2 micron filtration) with a foot pump? In my experience they slow the flow to 1-2 gpm @ 35 psi. I would think with a foot pump they would be unworkable. Pleated elements and granular carbon filters offer no real restriction, but since they don't filter microbes and in fact grow them, they have no place on a boat unless you really keep up with the chlorine.

[a64pilot]

Thinwater,
You asked a question, then answered it, and added an opinion. All may or may not have been outside of the original question's intent.
There are filters that are anti-microbial in that they will not support growth in the filter media, I have such a filter on my boat, but all I expect out of it is better tasting water

[Arthur Garfield]

Hi Guy,
Go these filters you write of desalinate or just larger particles?

[a64pilot]

Target,
I have a seagull as it came with the boat and after much deliberation I finally purchased the $94 replacement filter, I would have never considered it, except all the rest was already installed.
In my opinion the Seagull seems to be a good filter, but WAY overpriced, I think you can get the same result for much less money going with a standard housing and cartridge. Now, this is just my opinion.
You are only expecting better tasting water for drinking / cooking, your not trying to make non-potable water, drinkable right?

[Target9000]

Originally Posted by a64pilot

Target,
I have a seagull as it came with the boat and after much deliberation I finally purchased the $94 replacement filter, I would have never considered it, except all the rest was already installed.
In my opinion the Seagull seems to be a good filter, but WAY overpriced, I think you can get the same result for much less money going with a standard housing and cartridge. Now, this is just my opinion.
You are only expecting better tasting water for drinking / cooking, your not trying to make non-potable water, drinkable right?

The filter I'm looking for would provide better tasting water and filter most particulate out. I don't expect a filter to make water human safe, only more palatable. I have been looking at the seagulls and a knock off that is called the purest one. They seem to have good reviews.

Considering the time we plan on spending aboard, the price is not too extreme. The real concern I had was how well it would work with only a manual pump to pressurize it.

[a64pilot]

I think you'll have little trouble pumping water through a simple filter that is meant to get the big chunks out and improve taste with activated carbon.
I think if your concerned about "bug" growing on your filter, and maybe you should be, look for a filter that contains colloidal silver.
I also think you can get at least as good a filter as a Seagull for a whole lot less money by putting a "kit" together yourself. I believe all you would need is an activated charcoal filter in a standard housing and some kind of spout. Connect your pump output to a Y fitting, one end of the Y goes to the filter, the other end to your sink, whichever is open either the sink or the spout connected to the filter will get the water flow.

[Target9000]

While I agree it may be a high price for a filtration system, I simply don't have time to go on engineering it myself and shopping out the parts. I'm no expert on plumbing and fittings and filters. I have about 1000 projects to complete before we leave.

[model 10]

Originally Posted by Arthur Garfield

Hi Guy,
Go these filters you write of desalinate or just larger particles?

What do you mean by "large"? Not salt as it is very small but Chlorine, bacteria,metals etc.

[model 10]

Originally Posted by thinwater

Please clarify. Have you used a carbon block or ceramic filter NSF 53 rated to remove cysts (~ 0.2 micron filtration) with a foot pump? In my experience they slow the flow to 1-2 gpm @ 35 psi. I would think with a foot pump they would be unworkable. Pleated elements and granular carbon filters offer no real restriction, but since they don't filter microbes and in fact grow them, they have no place on a boat unless you really keep up with the chlorine.

Hey, I don't read the super fine print. The hard filters I have bought at Home Depot work just fine with our Whale foot pump. I have never expected our filter set up to do anything except further filter what is supposed to be potable water in the first place. Some of it tastes terrible.
Hooking up a water filter that you buy at Home Depot is not going to be any harder than hooking up one you buy from West Marine. I think the volume of the foot pump is so low that the filters pass water just fine. Our housing is clear and you can watch the process because there is some air in the housing. It looks like it is more of a displacement thing than a big pressure thing. I have stopped using the hard filters because they don't seem to be available in Mexico and Central America. At the low flow of the foot pump the regular cheap carbon filters last several months and the water tastes fine.