Back up portable water filter

[toddster8]

Some time back, Practical Sailor ran a story on an inexpensive “Baja Filter” type of device you can make to use when filling tanks. Works with gravity.
https://www.practical-sailor.com/iss...r_11660-1.html

Modifications I made were: an insert ring so that it can be run with two small filters or one large one. (I.e. if two-stage filtration seems warranted), end caps to keep dust out during storage, and a handle. Basically so it fits in the locker right next to my Baja fuel filter and looks like part of the set

[Sailor647]

Originally Posted by makobuilders

SAILOR, have you confirmed that the water receives enough exposure time under UV light, especially considering the high flow rate of a hose source?

The UV light requires a flow rate of less than 4 gallons per minute to effectively treat the water. We turn the dock water down to a trickle so the water has time in the UV filter. (We actually used a 5 gallon bucket to get the flow rate right in the beginning.) It takes hours to fill the tanks.

The unit we built is portable. It is stored in the aft lazarette after each use, with filters removed and all hoses and UV drained to help prevent anything from growing inside it. Even still, we have to clean the clear hoses and filter housings regularly.

It doesn't take minerals out of the water. We still have hard spots on the shower Plexiglas door.

It's interesting that the PPM meter doesn't show a significant reduction in ppm after our filters. (We know that the carbon filter adds particles back into the water.) On our next trip home this summer, we're going to take some of the raw dock water and some of our "filtered" water to a lab and have it tested out of curiosity. Hopefully, I can get two 3-ounce bottles of water through customs. LOL

[a64pilot]

I believe a lot of if not most of what a regular PPM meter will pick up is dissolved minerals.
They are called a TDS meter, the D stands for dissolved.
It’s pretty tough to filter out a dissolved mineral, a Watermaker of course does, but it’s a filter that is so fine by comparison that it’s ridiculous.

I may be wrong of course, cause if I’m right, what’s with this “zero water” filter that is sold?

[toddster8]

As I've posted elsewhere, I do test a lot of water from people's home systems in my laboratory. Very few home-installed UV systems actually reduce bacteria. Most cause a net increase. Of course, very few people read the directions. I suspect that the main problem is that people connect the UV tube so that "sterile" water flows into non-sterile plumbing, which immediately defeats the effort. But also the whole water filter market is a huge wad of snake oil.

PPM meters measure electrical conductivity, caused by DISSOLVED salts (ions). Particles have no effect on them, nor do particulate filters.

FWIW, I have had water samples taken from me by airport security. Some people have gotten them through. It seems rather random. When working on funded research, I've found it easier to ship samples separately by courier (relatively expensive) or military transport (free for government work). But if you want to test microbiological quality, you really need to do it on the spot - too much time and temperature variation during casual shipping. This kit does a pretty close approximation to lab testing for E. coli, which is the best known indicator for potential health effects, but it does require frozen storage for the reagent.

For most people, a bit of bleach in the tank is the simplest and best course of action, but some kind of particulate filter or strainer is still needed for dock water.

[ajchan]

We only filter our drinking water through a Seagull filter. The filters seem expensive but the unit provides excellent quality water and peace of mind.

Most of our water onboard is from our WM anyway somit is a bit of belts and suspenders.

A Seagull replacement cartridge is about $100 and lasts for at least two years so it’s not that expensive overall.

[mako]

I'm curious if anyone knows if those passive reverse osmosis filters that HomeDepot sells would actually produce fresh water from salt. I used to own one and it was great for just filtering tap water. It produced about 1 gallon per day of drinkable water, and threw tons more down the drain, but it worked on house water pressure (about 40-50 psi).

[kmacdonald]

Originally Posted by makobuilders

I'm curious if anyone knows if those passive reverse osmosis filters that HomeDepot sells would actually produce fresh water from salt. I used to own one and it was great for just filtering tap water. It produced about 1 gallon per day of drinkable water, and threw tons more down the drain, but it worked on house water pressure (about 40-50 psi).

No, they will not work for desalination.

[mikedefieslife]

I tried filtering water at the dockside with a 5 micron and carbon filter. It made it pathetically slow to fill the tanks. That makes it only suitable for use when staying in marinas.
It would be impossible to use when cruising in the Med if you fill up at fuelling stations or marinas which usually charge by time for filling water.

I have a General Ecology water filter in the galley, which works well and supposedly filters out viruses too. Some here seem to be sceptical of that claim, but the test data is there on the website. It reminds me of the Water-to-go flasks I used to use when motorcycle around South America. Again these filter down to the virus level, but you didn't half have to suck hard to get a good drink.

Not sure what the difference is between General Ecology branded filters and Seagul. They are both the same company. In any case I think it will be retired once the filter goes, as they are difficult to get hold of and are expensive. With the watermaker now in commission, they shouldn't be needed.

[LargeMarge]

Originally Posted by roverhi

[edited for brevity]
Use a little bleach in the tank...

I realize 'Better Living Through Chemistry™' is the mainstream 'instant cure for all ills', however...

We owned a restaurant for ten years. Sodium hypochlorite is corrosive to stainless steel.

Our tanks are stainless steel.
Our fittings are stainless steel.
Our faucet is stainless steel.

The leached minerals are suspended in the water.
These include nickel.
Consuming that in any amount sounds like a bad idea.
The point of purifying water == make it safe.
Safe water can be used for drinking. Cooking. Bathing.

I read about the delicate balance of intestinal flora.
Is ninety-percent of our immune system in our gut?
How much does our vagus nerve health effect our mental health?
How does bleach effect bacteria?

I wouldn't walk upwind of sodium hypochlorite without a moon-suit and respirator.
Can you imagine our largest organ == our skin == nicely opened and receptive while sitting in the chemical stew of a hot-tub? Or standing under a hot shower?

On a related note:
After exposure to plant irritants such as poison oak or stinging nettles, cold water closes the pores to reduce the absorption.

[Jimmyhenry]

We have used a 0.5 micron water filter for decades now, around NZ and around the Pacific islands. Minimal change in water pressure. Maybe that is because of pump size. it means we can take water form anywhere, and means we get no chlorine flavour or smell.
And the filters are cheap to replace. We buy by the box.

[Franziska]

Regarding a portable in-line filter set up when using a shoreside water hose.

Does anyone know which filter cartridge standart is the most commonly available?

Is there one which commonly available at a very reasonable price in the Caribbean and Europe?

Resources? Longevity?

I'm talking about a filter housing and the cartridges.

We think about a pre-filter, cat on filter and possibly a UV lamp as setup.
So two cartridge housings and the lamp.

This is for drinkable water.

[Merriweather]

We finally solved our water problems! We always had trouble getting water to fill up our boat tank when we are out cruising. We bought a "Rain Man" portable water maker and love it! It makes reverse osmosis water for drinking or for your tank. It makes the water straight out of the ocean water.
When we are at the dock we just use dock water to fill the tank. For drinking water at the dock we just filter the dock water with a ceramic filter.

[Nauticus]

Originally Posted by YachtBroker

Expensive but VERY good. You'll never buy bottled water again and removes all tank taste. Even old water.
I've had one on every boat I've owned, my house, my office, run the icemakers thru it etc. Filters last about a year or more. $100 each.

https://generalecology.com/collectio...roducts/732000

You're a legend! This is brilliant and perfect for my girl. Did you install it yourself?

Thanks
(I'm not often excited to spend 7 or 8 hundred)

Tim

[Merriweather]

The Rain Man water maker is portable so we don't really have to install it. We plan to eventually get to that. There are two parts to the water maker and they both weigh about 50 pounds each. We store them in our lazarette and get them out each time we make water. We usually make over 80 gallons in a few hours! It is the perfect solution to our problem of always running out of water when out cruising.

[Merriweather]

Oh I want to mention one very important thing re the Rain Man watermaker. You can only use it out in the sea! Never use it at the dock or in suburbia or it will be ruined! It's only good for converting sea water to RO drinking water in a place where the water looks fairly clean out in the ocean! It's like magic out there though!