Conference unifix::sailing

    Typical holding tank sizes vary with boat size. New boats these days
    typically use 20 gallons to about 35 feet then jump to 40 gallons in a
    36 foot. Here in Seattle there are two places that make them custom.
    Almost any shape you want like squares,rectangles, V-bottomed, etc.
    Most go for $120 for 10 Gal, $175 for 20 Gals, $240 for 30 Gals. This
    includes inlet, outlet, vent and cleaning port.
    

    Last month during the annual haul-out we replaced the two 10 year old 
    aluminum holding tanks on Viking Rose.  They were beginning to show 
    external signs of corrosion.  Aluminum is not a good material to be 
    used in this application. 
    
    We replaced the aft tank with a 30 gallon cube shaped plastic model 
    that fit into the existing space with minor modifications to the 
    woodwork. Cost was about $200 for the tank.
    
    We had a 20 gallon stainless steel tank custom built for the forward 
    head (as a bolt-in replacement to the old tank).  It is located in the 
    aft end of the vee berth, port side, and has an unusual shape.  Ballard 
    Sheet Metal (Seattle) built it for about $450.  We considered having 
    the inside welding seams coated with epoxy, but both the boat yard and 
    fabricator advised against it as an unnecessary expense given their 
    experience in building holding tanks.
    
    Additional notes: We have a macerator pump connected to each holding 
    tank as well as deck pump-out fittings.  We have no "Y" valves.  We use 
    Seazyme as a digestive agent in the tanks.  We replaced all head hoses 
    with the thick white hose that is now being used.  All of this has 
    yielded a "sweeter" smelling boat down below. 
    
    	Howard

    I put a Kracor plastic holding tank in last year. I reran all my
    lines with the new White hose and sleeve ends, similiar to the previous
    reply. I put in a Y valve as there are limited pumpout facilities
    in the Buzzards Bay area.
    
    The primary issues I considered in putting in the tank were; running
    the lines, having a cleanout access plate, the impact of chemicals
    on the cleanout pump, and the location of the vent.
    
    The access plate to clean out the tank at the end of the season was
    important. My wife is able to get her arm inside and use a soft brush
    to clean out any residuals. 
    
    The new white hoses seem to work very well. I purchased them from
    Jamestown Distributors. The Vent I put way up in the bow, and made sure
    the line always sloped up so there would be no chance of fluids
    collecting.
    
    I put in two Y valves. One to direct the output of the head either
    overboard or into the tank. Another to hook the outflow of the tank
    to the line going to the head outlet seacock. Basically with the two
    valves I can isolate the tank from the rest of the system.

    I am about to plumb in a holding tank system. Got the design nailed
    down except for one item. the holding tank vent. Originally I was 
    going to install it on the cabin top, but the folks at West Marine
    suggested I install it on the side of the hull, just below the deck,
    just aft of the center of the boat.  
    
    The person said if I mount it on top of the deck, the smell is going
    to come into the cabin while sailing.
    
    My only concern is what happens to the vent when that side of the
    the boat is the leeward side? Could the holding tank fill up, or would
    the rest of the system be closed?
    
    Should the vent line have a loop in it and would this help?
    If so, should the top of the loop be higher than the water line at full
    lean?
    
    Where is your vent tube located?
    
    Also, how high does one install the anti-syphon loop for the "real"
    piping. Right now I am going to almost the top of the cabin inside, but
    I would rather keep it lower and less noticeable if possible.
    
    thanks
    
    john

    
    John,
    
       If your mast is stepped on the keel, would it be possible to vent up
    the mast?
    
       /jim
    

    My vent is all the way forward in the bow. I put it on the inside of
    the fiberglass toerail, which is part of the hull deck joint. (Bad
    description but it is like a bulwark). But anyways I do not get any smell.
     You could mount it on the outside of the hull in the bow, as this very
     rarely goes underwater.
                                      Bill

    Not a holding tank question per se, but I couldn't find a topic with
    the title "Heads."
    
    Do any of you use a chemical head? Is one brand of chemicals better
    than another?
    
    Any suggestions/advice greatly appreciated.
    
    John H-C

    I am planning on adding a holding tank to Holiday II this off season.
    
    I currently have a Lectra San MSD.  I would like to take the ouput from
    the LEctra San and run it into the holding tank.  The holding tank
    would be as much as a foot above the Lectra San behind the head.  Sea
    cocks on each side of the holding tank will make it
    removable/replacable.
    
    The idea is not so much to replace the Lectra San as to go into no
    discharge areas and still be able to use the head.  Three year olds
    have a hard time learning flush the toilet, but not this time.  As a
    result the holding tank need not be large.  Further it is down stream
    of the Lectra San, so odors should not be a problem.  Out in the
    Sounds, open the sea cock and let gravity empty my holding tank. 
    Anyway, such is the idea.
    
    My real question is, will the output of the Lectra San push up the one
    foot or so of rise?
    
    Doug Claflin
    

    Doug
    
       FWIW
    
    
       Before you go the expense and effort (personal experience talking
    here), I would make sure that what you are doing is
    legal. West Marine doesn't think it will pass muster in all areas.
    It would be better to just put everything into the holding tank and
    then pump from there. You have to plumb for it anyways (grinder to
    holding tank), so plumb only to the tank. When you are out on  those big
    cruises, you would need to pump a second handle every now and  then.
    
       Do you really want to open up the seacock on the incoming holding
    tank each spring to regrease it?   (Yuck!!)
    
       Just think if the laws got strick and then you were trying to sell
    the boat. How much would a bad design cost you in selling price? Sure
    you could pull out the y valve and seacock, but would want to on a boat
    you were selling???
    
      

Good point.

I have not checked into the legal aspects.  This was strictly improving the
system and being more politically correct.  Boats are a great way to spend your
family fortune.

Part of the reason for putting in the inline holding tank, is that I already
have the MSD.  Works pretty good too.  To put a proper holding tank in requires
a fairly large area.  To put a "temporary" tank in is a much smaller
proposition.  I will think it through a little more this fall.

Incidently, I will be in Yankee Marine in Danvers this fall.  Holiday has been
there forever, along with Sam Dufour's B30 Tawney Loon.  They always put our
two boat together, and treat us well.  Further they are $25/ft.  Stop by some
time late Oct on.  

Incidently, if you use them, tell them I sent you.  I get some sort of discount. 
Like all mom n pop yards, these guys are really nice.

Doug