salt water flush vs. fresh water flush

J

jmeirhofer

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Pros and cons? Why would you want one or the other? Are they treated different? Is it difficult to convert from one to the other? Would you want to?

These and many other questions wake me up in the middle of the night. Is it time to go boating yet?
 
Fresh water if you have the tank capacity, a water maker or you are never far from a dock to fill up your water tank/s.

Some heads can run either. With salt heads it's important to put a inline filter on the incoming raw water line so organic matter doesn't build up under the rim of the bowl where it can rot and start to stink.
 
Been a long time since I ve had a boat with raw water head and I m glad I don't anymore. Even with a strainer, it smells after a while and it s yet another thruhull and associated below water line plumbing...

The only reason I see if the boat has grossly undersized water tank
 
Using fresh water means that you will need to carry or desalinate your supply. You may also need to have a presure pump n the system.

Using "raw water", you will gain another hole in the hull.

--

A raw water supply, if unfiltered ( typical ), will also suck up little tiny alive things, which get trapped in the intake hose and/or the inner, upper rinse ring of the head. When they die ( typical ), they smell. You will not have this issue with a "fresh water flush" system.

--

A fresh water system is not very complex, but a raw water system is simpler ( IMHO ). Raw water system often cheaper than fresh water system.

Note that in my experience, the odor from a raw water system was only noticeable for the first one to three flushes after a two or more day period of non-use. Others may, of course, have a more sensitive nose...
 
I have a Lectra-San unit & need salt water to activate treatment. Absolutely zero odor. Tickled to death with system.
 
I have the same concerns as mentioned. A hole in the hull and the potential smell. But a couple years down the road when the boat is back in fl I am thinking of a lectrasan with discharge ( another hole) for extended periods on thee hook in the keys and Bahamas and such. I have just over 100 gallons of fresh water. We do not drink or cook from the holding tank so it would be for dishes and showers. I would like to make that last a couple of weeks at a time.

Then again maybe the whole idea is nonsense to consider being out that long on an expess cruiser.
 
My Regal was a hand pump RWF. SMELLY in the bowl. However when at the dock, I merely used the hand held shower to flush.

Saint Max is a VacuFlush. No smell. However, newbies need to be tutored on how to use the system. I was shocked at how much water I went through with folks thinking it's just a toilet. Its all a tradeoff.

I believe the best of both worlds would be a RWF with a FW bowl fill to cut the smell.
 
John,

Watch that dream of a Type I MSD in FL as the Keys are NDZ.

The new Electro Scan is nice (less amps than the old Lectra-San). The Purasan is nicer in my opinion (if you want my Electro Scan, let's make a deal is it's sitting in my garage!). They both make boating 'more fun'.

If you want to be out that long you might want to get used to drinking out of your tank. It was built for that, so it can be quite safe. You can go with a Raritan Marine Elegance and get the option to have both fresh and raw water flush. Or, perhaps this will help since my boat is smaller than yours:

Fresh-water Marine Elegance head.
35 gallon fresh-water tank.
20 gallon black-water tank.
Water-maker.
Purasan (no need to worry about adding salt or dealing with the calcium build-up in the Bahamas that causes problem).

We spend 3 days per week on the boat in the MD summer and one month per year either in FL or Bahamas. We'll anchor for days at a time (6 is our record so far), and shower every day. So the question I pose to you isn't what source the water should be for your head, but rather what do you need to be comfortable on the boat? Being able to make water and treat the poo really makes life tolerable, even on a small 30' boat like mine.
 
As Kurt noted, the Keys and an increasingly large number of harbors along the east coast are NDZs. Silly in many cases, but that's the way it is. For these cruising grounds, you want a head that uses as little water as possible, because there can be extended periods of time when it is all going into the holding tank. Most of the NDZ harbors have pump out boats, but not the remote anchorages. We really like our VacuFlush fresh water heads, which have performed excellently in 4 1/2 years of living aboard. We installed a Watercounter on our fresh water system, so we are able to carefully manage our water usage. No watermaker, but 350 gallon capacity, but also have clothes and dishwasher on board. We lived full time on moorings for months, but again in harbors where they came to your boat and pumped you out every week.
 
Thanks for the info everyone. I am on a waiting list for a slip at Patrick AFB in Fl (2-4 yrs) so I have plenty of time to think about it. I don't think we would ever drink from the holding tank as we don't even drink tap water at home. I do realize you have to go "out" to discharged but i do however have a 50 gal waste tank. I was considering more for times of traversing between anchorages. I don't see us ever being out more than 2 weeks, maybe 3, so maybe I have enough of what I need already.

Obviously still a lot more to think about and even more to learn. :-)
 
I've got rw heads in my boat. It can smell in the heat, but we've found if you rinse and flush with fresh water after flushing with raw it is fine. It's nice cause it doesn't use up your fw as fast. Trade offs I guess.
 
I'd start thinking about garbage too if you are not using your water tank fully. Bringing drinking water in separate containers adds up. It's one area I can actually see some true "green" issues that are worth thinking about. On a boat it just gets painfully obvious too. Get a decent water filter and you will kill two birds with one stone.

Fresh water flush massively cuts down on the tinkering to keep the head smell down. Especially when you are getting back to the boat after being gone for a week. I also have a pursan attached to a hold n treat.
 
So you can't just throw all the plastic bottles overboard?

Just kidding. But it is a very good point and one I need to think about.
 
quote:
Originally posted by jmeirhofer

........ I don't think we would ever drink from the holding tank .............
Click to expand...


I wouldn't drink from the holding tank either. I do drink and cook with water from the potable water tank. It's fine. Been doing it for years.
 
quote:
Originally posted by jmeirhofer

Is it difficult to convert from one to the other?
Click to expand...


You cannot safely convert a raw water flush head to a fresh water flush head unles you install a seperate water tank just for the head and do not connect it in any way to the potable water system of the boat.
 
quote:
Originally posted by rawidman

quote:
Originally posted by jmeirhofer

........ I don't think we would ever drink from the holding tank .............
Click to expand...


I wouldn't drink from the holding tank either. I do drink and cook with water from the potable water tank. It's fine. Been doing it for years.

Click to expand...


FWIW, a contrarian view...

We only use the fresh water tank -- i.e., very, very seldom use the shorewater feed, and except for the occasional fizzy mineral water, we don't used bottled water either.

Our procedure is simple: starting with a clean tank... a household sediment filter used while filling the freshwater tank, and then a filter pitcher (Pur, I think, just now, but Brita is similar) for drinking, coffee, ice cubes, and some cooking water. A screw-on faucet filter would work for many; just doesn't happen to fit our faucet heads.

We also re-purpose a couple leftover softdrink bottles, fill those with filtered water and refrigerate, E Voila!

Using and refreshing water from the tank relatively quickly/often seems to be part of the equation... but in any case, the end result is the water tastes fine, freezes clear, etc.

-Chris
 
quote:
Originally posted by ranger42c

quote:
Originally posted by rawidman

quote:
Originally posted by jmeirhofer

........ I don't think we would ever drink from the holding tank .............
Click to expand...


I wouldn't drink from the holding tank either. I do drink and cook with water from the potable water tank. It's fine. Been doing it for years.

Click to expand...


FWIW, a contrarian view...

We only use the fresh water tank -- i.e., very, very seldom use the shorewater feed, and except for the occasional fizzy mineral water, we don't used bottled water either.

Our procedure is simple: starting with a clean tank... a household sediment filter used while filling the freshwater tank, and then a filter pitcher (Pur, I think, just now, but Brita is similar) for drinking, coffee, ice cubes, and some cooking water. A screw-on faucet filter would work for many; just doesn't happen to fit our faucet heads.

We also re-purpose a couple leftover softdrink bottles, fill those with filtered water and refrigerate, E Voila!

Using and refreshing water from the tank relatively quickly/often seems to be part of the equation... but in any case, the end result is the water tastes fine, freezes clear, etc.

-Chris

Click to expand...

I think you misunderstood my post or I am misunderstanding yours.

"I wouldn't drink from the holding tank either."

In my neck of the woods, the "holding tank" is where the contents of the head are "held" until they can be pumped out or discharged overboard.
Here's the rest of my post and I think it's about the same proceedure as what you describe:

"I do drink and cook with water from the potable water tank. It's fine. Been doing it for years."
 
quote:
Originally posted by rawidman

quote:
Originally posted by ranger42c

quote:
Originally posted by rawidman

quote:
Originally posted by jmeirhofer

........ I don't think we would ever drink from the holding tank .............
Click to expand...


I wouldn't drink from the holding tank either. I do drink and cook with water from the potable water tank. It's fine. Been doing it for years.

Click to expand...


FWIW, a contrarian view...

We only use the fresh water tank -- i.e., very, very seldom use the shorewater feed, and except for the occasional fizzy mineral water, we don't used bottled water either.

Our procedure is simple: starting with a clean tank... a household sediment filter used while filling the freshwater tank, and then a filter pitcher (Pur, I think, just now, but Brita is similar) for drinking, coffee, ice cubes, and some cooking water. A screw-on faucet filter would work for many; just doesn't happen to fit our faucet heads.

We also re-purpose a couple leftover softdrink bottles, fill those with filtered water and refrigerate, E Voila!

Using and refreshing water from the tank relatively quickly/often seems to be part of the equation... but in any case, the end result is the water tastes fine, freezes clear, etc.

-Chris

Click to expand...

I think you misunderstood my post or I am misunderstanding yours.

"I wouldn't drink from the holding tank either."

In my neck of the woods, the "holding tank" is where the contents of the head are "held" until they can be pumped out or discharged overboard.
Here's the rest of my post and I think it's about the same proceedure as what you describe:

"I do drink and cook with water from the potable water tank. It's fine. Been doing it for years."

Click to expand...


Ah, ooops, maybe I had a brain phart! :)

-Chris
 
I believe freshwater heads like the Marine Elegance (what I use) or the Vacu Flush have 2 advantages they use way less water for the flush cycle which has a direct effect on the number of flushes or content stored in the holding tank before it's full.
The 2nd is there is virtually no way for critter odor from a freshwater head.
My set up is (2) 40 gallon freshwater poly tanks (newer), a 35 gallon newer Poly 5/16 Holding tank, the Marine Elegance head, the Raritain Hold-N-Treat and a PuraSan. I also have a Spectra DC freshwater maker 6-8 gph when needed. The entire system draws very little current during the head's flush cycle, treatment of waste (when out of NDZ's) and making freshwater to refill the smaller tanks I installed during my upgrade.
Everything in a boat has to be thought of us a system. Meaning will the components fit, compliment each other, be reliable, draw low battery current and be legal.
Bill
 
Tell SeaRay that. My vacuflush system on our old 30'Sedan Bridge had only one water tank. I now have SWF and KNOW my water is safe.

quote:
Originally posted by rawidman

quote:
Originally posted by jmeirhofer

Is it difficult to convert from one to the other?
Click to expand...


You cannot safely convert a raw water flush head to a fresh water flush head unles you install a seperate water tank just for the head and do not connect it in any way to the potable water system of the boat.

Click to expand...
 
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