Conference unifix::sailing

    At the begining of each season we put sodium metabisulphate into
    the tank ,fill the tank and let it stand for 24 hours. We then flush
    the tank through three times. We have an inline chemical filter
    from the tank to the galley pump, this also gets replaced each year.
    During the season we keep the tank topped up wherever possible.
    We always let the hose run for a few minutes first before filling
    the tank. Our water is used for drinking as well as washing etc
    it tastes fine. Maybe you should flush your tanks through, then
    sterilise them etc. The inline water filters are very good and worth
    a try.
        
    Pete
        

What are your tanks made of? Ours are stainless steel. We've never had 
any problem with water quality. We don't use any purifying chemicals, 
have never flushed the tanks, and have no filters. 

If you have fiberglass tanks or tanks made of some translucent material 
I suppose that there might be enough light in the tanks to allow algae 
or other stuff to grow. Water tanks also shouldn't be made of aluminum.

Alan

    Alan,                                             
        The reasons for all the tank sterilisation is thus 
        
    - The water tank gets drained at the end of the season our winters
    in the UK are relatively mild and thus condensation can occur in
    the tank. The tank is vented and thus I am told nasties can over
    the winter develope that can cause the water to foul. Thus each
    season the sodium metabisulphite rids us of the nasties. (Sodium
    metabisulphite is the chemical we utilise for sterilising our Wine
    & Beer making kit......) The advice to do this came from a friend
    who is a yachting doctor.              
                                           
    - The use of the inline filter came about from another "Yotty" who
    took 3 years off to sail the Oceans and recommended it to us. It
    simply makes the water taste better by filtering out some of the
    chemicals that are put into the water supply system both in the UK and
    Continental Europe. Sensible for us as we tend to cross the channel to
    France two or three times a year and fill up at sundry French &
    English ports.  
                                           
    I have just spoken with the mad medic who believes that once a tank
    has been fouled it needs to be sterilised. You can in very hot weather
    get Algae growth in the tank to pump pipes. Not much chance of that
    over here tho.......
        
        
    Pete                                       
                                           
                                           

 
At the beginning of the season I flush the tank and then add a little 
(less than  1 oz. per 30 gal tank) clorine bleach to a full tank.  I let this
"clorinated" water stand for at least 24hrs and then flush it again.  I 
usually repeat this procedure later in the season.

In the winter I drain the tank and run a couple gallons of the non-toxic
anti-freeze through the system.  (I drain and bypass the hot water tank too.)

Note that I don't use my water tanks for drinking water. I have a 5 gallon jug
for that.  I also keep a 1/2 gallon container topped off in the icebox.  It's
been getting alot of use these past few weeks!

bc
 

    I am a big believer in not fixing things that are not broken...
    
    My boat has "transluscent material" tanks (poly-something or other)
    which have never shown any significant problems with algae
    build-up, foul taste, or any other problems.
    
    My last boat had a similar tank which we fought with all the time
    to keep the water clear.  The only difference I can state for
    sure existed was the first boats tank had some light in daylite
    hours, the current one does not permit any light.
    
    I have filled this boat from water systems in Ct., RI, NY, and Ma.
    
    I looked at water filter systems but never found a need.  I also
    do nothing remarkable (in my opinion) to maintain them.  Each fall
    I scrub the inside of each tank with a wash cloth and baking soda,
    followed by a couple hose-down and pump outs.  I add no anti-freeze
    (I did the first year but I decided that cure was worse than the
    problem) since I can drain the whole system by disconnecting the
    inlet and outlet of the pump (I really believe money spent thinking
    thru subtle thing like the water system component location is more
    important than hiring a decorator to design the interior of the
    latest floating condo tub).  In the spring I add water and go. 
    
    One last thing that I do which could make a difference. I seldom permit
    water to sit in the tanks more than a couple weeks. I do that by
    emptying a tank thru use before refilling, and I only fill according
    to predicted use. This doesnt work out too well if your source of
    water is unpredictable, like on a mooring or half way across the
    Pacific.
    
    I have carried a bottle of Clorox for 5 years just in case the water
    did turn on me (at least I could kill the live stuff) but so far
    have only used it to kill mildew and remove stains elsewhere.
    
    Walt 

    I performed the winter purge and flush with potable antifreeze,
    making certain that the antifreeze ran out all faucets (to prevent
    any fresh water traps from bursting).  The water was fine until
    a couple of weeks ago, when we first noticed it.  It seemed to take
    two weeks to form this odor (as we weren't on the boat for a two
    week stretch in July).  The last fresh water fill took only a couple
    of days to develop the odor.
    
    I think I'll try adding chlorine to the system, letting it sit,
    then flushing it out.
    
    By the way, the tanks ARE translucent and made of some type of plastic
    material.  They are, however, buried under the settee's so I don't
    expect much light could get through to them.
    
    Thanks for your help,
    Al ('First Time', west side Marblehead)

Though they seem difficult to find these days, water purification tablets 
do a marvelous job of killing any living odor auses, without adding any 
taste or bad stuff to you or the system.  Just drop the appropriate dosage 
in the top of the tank, and let the natural sloshing do its thing. It's 
easy, and there's no chlorine or other taste.

J.

    A mail/telephone order Company in UK that accepts over the phone
    all major credit cards called CRUISERMART UK 0702-460055 has a standard
    entry for AQUA TABS described as Water Purifying Tablets a 32 tablet
    pack that treats 5 gallons costs 2.5 Pounds expensive .The next
    item is PURICLEAN for a complete system a few times through on a
    20 gall system costs 3 Pounds. However I rather go to my local home
    brew shop and get sodium metabisulphite for approx 0.7 Pound per
    20 Gall tank. (Gallon size is imperial not US variety....)
      
    P.

    My first boat had fiberglass tanks and in the warmer months had
    the "growth" problem.  It did not appear to be algae, but it was
    a clearish scuzzy substance in the tanks.  I used one capfull of
    Clorox per tank and never had the problem again.  The water did
    have a slight clorine odor, but little taste.
    
    I have not had the problem with my current boat with the stainless
    tanks.  I do not use antifreeze because of the difficulty in getting
    rid of it in the spring.  I drain the tanks and blow the lines out
    with air from my scuba tank (using stage one only of a two stage
    regulator).  This has worked well for the five years with this boat.
    

    Took a closer look at this during vacation last week.  The odor
    is only present when we turn on the Hot water tap; the cold water
    seems to be fine, so I don't think the tanks have a problem.  The
    hot water, however, definately turned sour.  We have a 6 gallon
    hot water heater (heat exchanger from the engine cooling system).
    I added a capful of Chlorox to each tank, ran the hot water tap
    until the odor cleared.  Seems to have taken care of it, we'll find
    out this weekend.
    
    Thanks for all the help.
    Al

    
    I'll second Walt's suggestion of putting only as much water in the
    tank as you think you'll need (fine for short cruises and daytrips).
    
    A second benefit of this approach, depending on the size of your
    water tank, is that you have less weight and therefore the boat
    should sail a little higher and faster...  probably not too 
    significant, but every little bit helps.
    
       - Jim
    

    Seems like there is a lot of good info & suggestions here; but,
    I couldn't resist putting in my 2 cents worth.
    
    Some things I couldn't understand - Like why are some folks afraid
    to drink out of their water tanks?  Isn't that the main purpose?
    I also view the hot water tank as a mere extension of the main (cold)
    water tank.
    
    I have had "plastic" tanks on both motor homes and boats for 18
    years and never had a problem unless I had bad water to Start with.
    
    Some general things I do and rules I follow are:
    
    - CLEAN THE TANK (inc. Heater) in the Spring
      I 3/4 fill the tank and add about a cup of clorox bleach. Then
      go for a ride to mix it around.  Fill & Empty a few times to clear
      out most of the clorox.  Then 3/4 fill & add a small box of Arm
      & Hammer - let it sit over night (a week...) to sweeten the tank.
      Then empty & fill for use.  Remember while doing this to run water
      out both the cold & Hot taps (i.e. do the heater)
    
    - USE THE WATER SYSTEM frequently.
      Water will go stale.  It will turn faster if warm -- hot summer
      days or the heater (I think much of this is due to always present
      bacteria that dies due to lack of oxygen -- again this would effect
      the hot water system first as it has no vents).

    - ONLY ADD WATER WITH YOUR HOSE & never use an all rubber hose.
      I have found that the few times my tank went bad it was because
      I had used a hose sitting there that was a real good flexible
      expensive rubber one.
    
    - KEEP THE TANKS FULL - mildew grows in dark warm moist places like
      the top/sides of a half full tank -- it does not grow in water.
      If you leave for an extended time Empty the tank & refill upon
      arrival
    
    Well thats my method.   One side point is that a quart of any
    reasonable Vodka will normally sweeten even the worst of tanks.
    (Really)
                               Fair winds,
                                           Capt'n Lou "Phanta Sea"
    
    p.s. Al was warned about this one.  If he used his boat perhaps
         it wouldn't go stale!  :-)

re .10:

Just the hot water? Hmmmm, does your hot water heater have a magnesium 
rod inside to prevent corrosion? Certain kinds of water react with the 
magnesium in such a way as to produce a rotten egg (hydrogen sulfide) 
odor. We had this problem with both our house water heater and the 
orginal heater on the boat. Removing the magnesium rod solved the 
problem in both cases.

Alan

    re .13
    
    You have correctly identified the odor.  I can't recall what material
    the tank anode is made of, it could very well be magnesium.  The
    interesting part is that the odor occured just after I added Arm
    & Hammer to the tanks (as suggested in .12)!!  The water was fine
    during the '87 season and during the '88 season until July, when
    we added the baking soda to 'sweeten' the tanks.  Is this coincidence
    or could the baking soda react with something to cause the odor?
    It is ONLY in the hot water line; after we run enough water through
    the hot water tap (~6 gallons) the water clears up.
    
    I'll check to see if we have a magnesium rod in the tank.
    
    P.S. (Thanks, Cap'n Lou, but just be cause I only have 40 hours
    on my engine doesn't mean I don't use my boat;  most of us in this
    conference use wind-not fuel :-)  )
    

    Almost five years since an entry in this topic. Does anybody have
    improvements on the techniques suggested here? I'm about to "refresh"
    the 20-gallon tank in my boat. It hasn't held any water for more than 5
    years, so there's no telling what has taken up residence in there. (It
    spent most of that 5 years at anchor in the steamy air of Mobile Bay.)
    
    I was advised to give it a good rinsing with a fairly high
    concentration of Chlorox, followed the next day by a fairly high
    concentration of baking soda. I saw the same recommendation in an
    earlier reply here.
    
    Does that still seem like the best way to "renew" a tank?
    
    Thanks.
    
    John H-C

    John, you did not say, what type of tank you have. If its stainless,
    follow any advise and you will get it clean one day.
    
    If its plastic, buy a new one. 
    
    
    Peter

    Can't plastic tanks be properly cleaned?  Why buy a new one rather than
    clean it?

    
    	When I purchased my (used) boat the fresh water tank was filthy!
    Its plastic and I did not replace it. I used a bleach water combo and
    threw in a few towels whiched when sloshed around helped with the
    cleaning action. I think I did 2 tankfulls of the bleach/water and then
    a tank of fresh stuff and I have no complaints. I still would not drink
    from the tank but for cleaning hands/dishes its fine. Bottled water
    brought from home is used for drinking.
    

    re .18
    
    you said it. You can not drink it. 
    
    I operated my desalinator in Rodney Bay St.Lucia and two days later,
    both (bladder) tanks smelled terribly. I cleaned both, but the water
    still smells strange after 2 years. The water itself is ok, but I
    never got the rotten smell completly out of the system.
    
    We have no problem with it. We never drink water in the first place;
    coffee and tea is made from either bottled water or we fill a jerrycan
    directly from the desalinator. 
    
    I have friends who also tried unsucessfully to clean plastic tanks and gave
    up. Since our accident in the Rodney Bay, we carry now always a pack
    of dishwasher cleaner. This is in my opinion the safest, nontoxic way
    to clean watertanks. 
    
    Peter

    I guess you can count on the Swiss to come up with an ingenious
    solution. <g>
    
    Peter, what brand of dishwasher soap do you use? Does it lack
    phosphorus and its compounds?
    
    Would the same stuff work in a metal tank, do you think?
    
    Thanks.
    
    John H-C

    Hi John,
    
    I have just the ordinary powder we use everyday in our dishwasher.
    
    I cleaned my jerrycans with it. Because they started to have some green
    growth in them.
    I put in a teaspoon of dishwasher in the canister and added water. Wrong ! 
    I had a hard time, to get all the crystals out. For the second
    canister, I disolved first the powder and had no problem to get rid of
    it.
    Stainless steel tank ? Usually this tanks have an inspection opening.
    No problem in cleaning them with just ordinary soap and brush.
    If it has been 5 years not in use, I would try to remove the tank 
    and clean it at home until it stops smelling.
    
    Yes, I know, such simple tasks like removing a 20 gallon tank for 
    cleaning may consume a day or more. Not removing, may need several
    days to get it clean....
    
    Peter
    
    
    
    
     

    re: .15
    
    If the water tank is made of aluminum, I would not use baking soda.
    I believe that baking soda reacts with aluminum.
    
    Joe

    Hmmmm, good point. I know grapefruit juice (acidic) does, but baking
    soda would be an alkali.
    
    Jeff

    Aluminum reacts with water.  What protects it is a thin coating of
    oxide formed when the aluminum is exposed to air.  Baking soda will
    attack this oxide layer exposing the aluminum which then reacts with
    the water.
    
    Ken

re aluminum water tanks:

Because aluminum does react with various chemicals commonly found in 
drinking water, aluminum should not be used for drinking water tanks. 
Early Valiants had aluminum tanks -- my understanding is that all of 
them were replaced under warranty with stainless steel tanks. Our 
stainless steel tanks have been most satisfactory. In 13 years the water 
has always been quite drinkable, except for one time when an over 
zealous crewmember dumped in too much bleach because we were uncertain 
about the quality of the water. 

    Because of some severe crystalazation in the supply, I opened the
    inspection ports of the aluminum tanks and found a great deal of what I
    assume is mineral deposts in the tanks.  My marina uses well water so
    the mineral content is high.
    
    I am going to write Caliber on how best to clean these, but I thought I
    would see if anyone has any suggestions.  Previous notes would indicate
    aluminum is sensitive to many products that come to mind for cleaning.
    
    Replacement is an unpleasnst option as it would require removal of the
    entire cabin sole.
    
    

    Vinegar or other mild acid solution.  Whatever that stuff is they use
    to clean tea kettles.
    
    Brian

    re:.26
    
    Viking Rose carries 350 gallons of water in four aluminum tanks. We
    also notices that there was a build-up of oxidation and other nasty
    looking stuff inside the tanks.  We had them pressure washed then
    scrubbed with a mild acid solution. They looked squeeky clean after
    this treatment.
    
    We didn't stop there however. Because we found that one of the tanks
    had developed a pin-hole leak, and there were signs of similar
    corrosion developing we decided (after much research) to have the tanks
    primed and epoxied on the inside.  This is a bit of work, but the
    result is tanks that look better than new, there are no leaks, and none
    of the aluminum oxide floating around in the water (which is considered
    by some to be a health hazard).
    
    We will be returning to Seattle next March and will recommission Viking
    Rose and will probably be living aboard part-time.  Time will tell how
    effective this repair will be in the longer run.  I know that epoxy
    will not work well on stainless steel, but the tests on aluminum that
    had been properly prepared were positive.
    
    I have details of the exact process and products that we used. If
    anyone is interested I can post here, or send via E-Mail.
    
    Howard

    I have the two 75 gallon tanks clean and dry.  The amount of white
    crystals, which I assume is calcium, removed from the bottom of the
    tanks was very high.  
    
    Several places the deposits were so attached to the tanks, I had to
    scrap them off with a putty knife.  The baffles in the tanks make total
    access impossible.  The welds seem particularly vulnerable to the
    depostis.  The deposits are very similar to some clogged pipes I had in
    my house when I lived in San Diego years ago.  Again very high mineral
    content.
    
    Gerorge McCreary at Caliber had few suggestions other than not using
    hard water.  I guess I could call Culligan and find out what additives
    I could use to reduce the minerals.  
    
    The problem seems to have peaked this year, although the buildup could
    have been going on for years.  I guess I will do annual inspections to
    get a better feel for what's going on.  The filter before the fresh
    water pump should be another indicator.
    
    Any other suggestions are welcome.