How much water do we need?

[newhaul]

Originally Posted by Stu Jackson

That's true, but essentially the OP asked to find out if the one that's on the boat is adequate for their intended use. The general conclusion was that it was way small.

It's like: I am considering a boat with 1 Grp 24 battery and intend to cruise offshore without solar or an engine. Do you think I'll have enough power?

Its a GRP 27 battery and have 15 watt solar to charge it

[downunder]

Originally Posted by SV THIRD DAY

Our family of 4 has been using 20-25Gals/day of water now for about 7yrs. Sure we could use 10-15/Day, heck maybe even less if we had to, but just like power, you will adjust your water usage to what you have. Now me, I couldn't survive in 90+ heat and humidity without my shower after the morning boat projects and shower before bed....but hey, I'm a water whore and love it.

As a high output water maker pusher.

• I don't sell daily or even twice daily showers when it's hot and sticky.
• I don't sell Deck and Gear wash downs at anchor

What do I sell?

• Romance Aboard Baby!

Guys, if you haven't figured out that the chances for romance while cruising and living aboard are directly proportional to the cleanliness of your body, then I give up....You might as well become a monk. And NO....most wives are not going to count a salt water swim, or Hudson garden sprayer shower as really having a "clean body", so you can forget that along with your underway cockpit fling!

I've chatted water makers with a lot of cruisers and I just don't remember someone telling me "Rich, I went with too large a water maker, I should have bought a smaller one" or "I have too much solar aboard".

Well I think you have got to the crux of it. Romance.



Some of the posters recommending none or low capacity cruise by themselves.

[zboss]

We tried it but I'm not a big fan of catching rainfall. We have a lot of birds in the [few] places we have been and you need to make sure your surface being used to catch water is sparkling clean.

If we were in a far out place with no access to water, I'd try it again but I think we will just stick with our 60 gallon water bladder and pump. Takes about 3 hours to fill our 150 gallons which lasts us a month or more without extensive showers.

Maybe what we could do is plumb the rainwater from the boom tent into the bladder, treat with bleach, then pump through an RV filter into the tanks.

We will probably go a high capacity watermaker because we love being able to wash down everything with fresh water - getting the salt off the boat makes living on the boat much more pleasant.

[Sandero]

It depends doesn't it? Cruising coastal in NE for example you can get all the water you need at many fuel docks and marinas. The only problem is getting a slot to fill up because there are many doing just that!

For passages you need a few gallons per person per day maybe... depends on how much you use.

[newhaul]

Originally Posted by downunder

Some of the posters recommending none or low capacity cruise by themselves.

Its me and my dad when cruising while I do say the 35e is sufficient I'm not advocating small units per say however I don't really see a need for more than say 4 or 5 gph output the 20 gal per hr units don't really make sense for me if I was purchasing a new unit I would go larger but the 35 came with the boat including two of the long range cruising maintance kits and a new spare membrane and all cleaning kits and compounds someone wants to sell me an old 35 or 40 cheap I would jump due to having all the rebuild parts and I would add it to current systems

[ebs001]

I have a Katadyne 80e for about 7 years. If I were doing it again I would buy a larger capacity unit but I knew little at the time. I definitely agree the 40 is way to small. With two of us aboard we use about 4 gallons per day. We are not particularly frugal but we watch our water consumption. We have showers regularly using a solar shower when we ate not plugged into shore power. We have relatively small water capacity so the watermaker means we have freedom to be in remote places where there is no potable water. It also saves us lugging jerry cans around and buying water.

We are very happy that we have a watermaker for our cruising life style.

[downunder]

Originally Posted by newhaul

Its me and my dad when cruising while I do say the 35e is sufficient I'm not advocating small units per say however I don't really see a need for more than say 4 or 5 gph output the 20 gal per hr units don't really make sense for me if I was purchasing a new unit I would go larger but the 35 came with the boat including two of the long range cruising maintance kits and a new spare membrane and all cleaning kits and compounds someone wants to sell me an old 35 or 40 cheap I would jump due to having all the rebuild parts and I would add it to current systems

No criticism of anybody's choice but essentially everybody who goes small says as you do. "If I was purchasing a new unit I would go larger".QUOTE

So I think the best advise for someone that doesn't have one is to go to some that puts out 20-30 gal/hr particually as they are often not necessarily more expensive.

[clownfishsydney]

My wife and I came into sailing after a long period camping using our Toyota 4WD to visit remote parts of Australia. If going to the high country, lots of water was available, so we could use as much as we wanted for hot showers (we have hot water heat exchanger in the car).

However, on trips to Central Australia, we often went a week or more without the ability to get additional water. In those cases, we were limited to what we could carry, a maximum of 50 litres (13.5 US gallons). This would easily last us that long, with very quick and short hot showers every second day.

On the few sailing trips so far, we have been trying to work out how much water we can use without been too frugal and how much if we have plenty to spare. We carry 455 litres (135 gallons) in three tanks and 100 litres more in Jerry cans. Over Christmas we tried to see how we went with quick hot showers every few days, cold deck showers after the last swim of the day. We ended up using 175 litres (47 gallons) over 10 days, so 8.75 litres (2.4 gallons) each per day. This was quite comfortable for us. Therefore we have enough water on hand to last us over 30 days at that rate of use.

As we have a Spectra watermaker, we will not need to be that frugal, but since we intend to do some long passages (with more crew) later, it is good to know how long we can last.

[richard_wb]

Questions about water maker capacity often seem to be based on the assumption that if someone installs a water maker, it will be the only source of fresh water. That's an unnecessary assumption. If you think of a water maker as one of several fresh water sources, you might decide that a smaller one is adequate. I have a Katadyn 80E, which when cruising I didn't like to run more than 1 or 1.5 hours per day, because my solar capacity was a bit undersized and most of it's output went to keeping the fridge/freezer running. But a combination of water maker water, captured rain water, and occasional fill-ups from shore-side provided adequate water for our needs.

[mitiempo]

One factor is location - for example the Sea of Cortez where rainwater basically doesn't exist.

Another issue is capacity. Smaller boats do not have the capacity to carry as much water as larger boats.

Owning a smaller boat - 27' - and planning to cruise the Sea of Cortez in a few years I will be taking a watermaker. One that is efficient in power usage and has a reasonable output. The 40E loses on both counts.

It will be a small Spectra - 6+ gallons/hour.

[Tellie]

Originally Posted by mitiempo

One factor is location - for example the Sea of Cortez where rainwater basically doesn't exist.

Another issue is capacity. Smaller boats do not have the capacity to carry as much water as larger boats.

Owning a smaller boat - 27' - and planning to cruise the Sea of Cortez in a few years I will be taking a watermaker. One that is efficient in power usage and has a reasonable output. The 40E loses on both counts.

It will be a small Spectra - 6+ gallons/hour.

Cheap plug alert.
Come on down to the Miami boat show next week. I'll be raffling off a new Spectra Ventura 150 at the cruisers party Saturday night. Just what you're looking for. Be great to see you there.

www.HaldenMarineService.com

[tmoandj]

So, I was looking at the specs for the katadyn 80e. Am I reading correctly that its 4 gallons per hour and 8 amps per hour? In other words, 8 amps per 4 gallons. If I'm using 20 gallons a day its going to cost me 40 amps a day? That seems like a lot doesn't it? I'm trying to avoid running the engine but is this feasible?

Sent from my SGH-T989D using Cruisers Sailing Forum mobile app

[richard_wb]

Originally Posted by tmoandj

So, I was looking at the specs for the katadyn 80e. Am I reading correctly that its 4 gallons per hour and 8 amps per hour? In other words, 8 amps per 4 gallons. If I'm using 20 gallons a day its going to cost me 40 amps a day? That seems like a lot doesn't it? I'm trying to avoid running the engine but is this feasible?

Sent from my SGH-T989D using Cruisers Sailing Forum mobile app

The specs for my 80E say 3.5 gal/hr at 8 amps. That probably assumes batteries are fully charged. Twenty gallons per day for 3 people seems like a lot to me, but everyone's desired usage is different. Cruising, to me, means letting go of resource usage that we're used to at home, where we're connected to unlimited supplies of water and power. You might be surprised at how little water you need for a shower if you wet yourself, shut off the water to soap, then turn it back on for a quick rinse.

[tmoandj]

So, how much do you use yours? Do you run it for a bit every day? How many amps does it burn?

Sent from my SGH-T989D using Cruisers Sailing Forum mobile app

[richard_wb]

Originally Posted by tmoandj

So, how much do you use yours? Do you run it for a bit every day? How many amps does it burn?

Sent from my SGH-T989D using Cruisers Sailing Forum mobile app

When I was cruising the S. Pacific with two people aboard, I ran it 1-2 hours/day.

The important issue to focus on is your electrical capacity. The amount of water you're going to be able to make is completely dependent on your battery/solar/turbine/alternator capacities. If you're going to the tropics you might be surprised at how much power your refrigeration will consume.

Regarding how many amps the 80E uses, the spec says 8 amps but its a bit hard to know for sure because the draw isn't steady...the amp meter swings back and forth with each cycle of the pump piston, so you won't get a single, steady number from your instantaneous readout meter. Katadyn claims the 8 amps is an average.