Raw water pre-treatment of head flushing water

Discussion in 'Sailboats' started by jamesgyore, Jun 21, 2013.

  1. jamesgyore
    Joined: Sep 2011
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    Location: Melbourne

    jamesgyore Senior Member

    I honestly have no idea were to most appropriately place this question... But here goes...

    I, like a great many people, have elected to go with a head flushed with sea water. I don't have sufficient potable water storage or the ability to make potable water on demand to have any other option.

    I also have had to deal with the awful stench of micro organisms that thrive in sea water flushed heads in the past... So help me, I will not suffer through THAT again.

    I'm quite familiar with simple chemical treatment/process strategies that dissolve calcium based variants resulting from urine chemistry and sea water interaction in head plumbing using low dose acid treatment.

    The question is... Without resorting to fine-micron filters (not replaceable mid voyage), UV radiation (high energy demand), O-Zone generators (high energy demand), or chlorine generation by way of electrolysis (high energy demand):

    Does anyone have a simple DIY recipe for making a slow release/dissolving "hockey puck" that could be moulded or caked into a cheap off-the-shelf filter/strainer enclosure to achieve raw water pre-treatment of head flushing water?

    DIY is the keyword... I'm not interested in off the shelf products I can't get from the US because the word chlorine appears somewhere on the invoice and some customs idiot assumes I'm a terrorist threat to my own boat... Or maybe his.

    I'd rather deal with the problem and not the symptom, so head-ache causing deodorants like stench of pine forest or fields of lavender just won't cut it.

    I was mulling over the problem after a few beers and thought perhaps a dry granular chlorine encased in a water soluble gel in progressively thick layers to withstand 1 to x number of flushes might do the trick.

    Likely I'm over thinking the solution. Does anyone have thoughts or ideas?


  2. micah719
    Joined: Jul 2012
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    Location: Somewhere in Germany

    micah719 Plotting Dreamer

    Why not dodge the whole shipload of problems with a stinky seawater head and holding tanks and pumpout receipts and possible leaks, and get a composting head? All you need to run that is peat moss or leaf litter, and keep it ventilated (flettner rotor and/or a little solar/battery fan).
  3. michael pierzga
    Joined: Dec 2008
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    Location: spain

    michael pierzga Senior Member

    well...you know the problem. Biological growth...rotten egg smell ...in the sea water supply lines.

    I dont know the solution. I use fresh water to flush heads.

    Perhaps there is somekinda magic filter or zapper to purify the sea water.

    Something to consider.

    Ive used plenty of sea water flush heads .

    If you do plenty of pooping and frequently flush, the smell is not an issue. If you let the boat sit...no pooping...for a long time ,then count on rotten eggs.

    The secret is plenty of flush action.

    I suggest you Develope a taste for Greek food and carry extra toilet paper.....this would be the cheapest way to avoid rotten egg syndrome.

    Toilet paper is cheap...Greek food aint that bad going in and rapidly blows out within an hour or two.
  4. sdowney717
    Joined: Nov 2010
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    Location: Newport News VA

    sdowney717 Senior Member

    yes, it did stink in our boat UNTIL, I added a small water strainer I bought on Ebay.
    The strainer screwed directly to seacock.
    It is black plastic with a small screw on clear bowl and a fine SS mesh screen. It is for 1/2 inch NPT thread pipe.
    Why it works, I think is it keeps out the small sea life which otherwise dies in the hose-head-pump, rotting and then releasing gas when you pump the head.

    So I happily use salt water flushing.
  5. tomas
    Joined: Nov 2012
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    Location: California

    tomas Senior Member


  6. jamesgyore
    Joined: Sep 2011
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    Location: Melbourne

    jamesgyore Senior Member

    You might well be right.

    Micron fine filters are better at removing bacterial and viral loads from a solution than R/O membranes.

    Perhaps a S/S mesh basket will do the trick, in which case a commercially available urinal cake within the basket would be more than adequate.
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