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  Topic Review (Newest First)
10-07-2008 01:31 PM
RAGTIMEDON In a fiberglass or plastic tank, you can add a teaspoon of bleach to each gallon of water put in the tank. It will keep mold and bacteria from forming, but may taste/smell bad. The undersink filter from Home Depot will take out the smell and deliver good water for drinking, coffee, etc. Leave the bleach in the hot water lines, it will sanitize your dishes and won't hurt when you wash your hands. DO NOT do this in an aluminum tank! An annual chlorox shock and cleaning, followed by thorough flushing, will not destroy the aluminum, but long term exposure to bleach (even in small concentration) will. Every few years you will want to do a mechanical scrub inside the tank, whether plastic or metal. A gasketed screw-in deck plate can be put into the tank easily. My tank is 100 gallons, aluminum, horizontally mounted in the bilge, with two baffles in it to cut down on sloshing. I had one access hole, and after I cleaned as much as I could reach, I cut in two more access ports between the baffles with a sabre saw. There was an inch of crud on the bottom of the tank between the baffles! Until I bought the boat, the tank had never been properly cleaned in 25 years! I do an annual inspection, chlorox shock and flush, then keep it pure with an iodine based sanitizer. This routine is probably not as critical for a live-aboard, due to the higher usage, but as a weekend warrior and laid up for 4-5 months in winter, the water tanks can get pretty gross.
10-07-2008 11:54 AM
Idiens Bi carbonate of soda (baking powder) is also used to clean out fresh water tanks.

I've seen that black stuff (usually black mold) formed inside the water inlet pipes even on quite new boats, the transparent inlet pipes and the sloshing water really encourages it. Whereas it's not so keen on the submerged areas. Maybe you can get a long bottle brush to tackle the inlet pipes.
10-07-2008 11:43 AM
Skipaway What about using Iodophor as a sanitizing agent? Available at home brew shops and I'm sure many other places.

Iodophor - Wikipedia, the free encyclopedia
10-05-2008 09:29 PM
sailingdog Repeated use of chlorine bleach is not a good idea for aluminum tanks, but a properly done annual shock treatment shouldn't be a problem.
10-05-2008 09:00 PM
camaraderie Bleach will not hurt the aluminum if it is used diluted as specified and properly further diluted and flushed from the tanks.
10-05-2008 05:56 PM
FrankTugw2ell If your tank is aluminum, don't use bleach. It will attack the aluminum, I am sorry to say. You might try a gallon of cheap Vodka, which will not hurt the aluminum, but which will attack fiberglass. Use chlorox if the tank is fiberglass, but not aluminum.
09-24-2008 03:31 PM
sailingdog Depends on where the fill port on your tank is. If it is at the bottom of the tank, then the last few inches of fill hose can get very grungy...

Originally Posted by welshwind View Post
I wouldn't think you really would need to replace the fill line. In normal installations, water would never sit in it like it would the supply line from the tank to the sink.
09-24-2008 11:28 AM
welshwind I wouldn't think you really would need to replace the fill line. In normal installations, water would never sit in it like it would the supply line from the tank to the sink.
09-24-2008 10:29 AM
hose gunk

You can get the tank spotless and disinfected, but if you take a look at the hoses you will gag. They really don't seem to come clean. You will need to replace them, including the fill, though the ones that run horizontally are the grimiest.
09-23-2008 07:36 PM
CrackerJacks I had a similar situation>I was told to put a quart of cheap Vodka in the tank. I let it sit and then pumped it out. Worked well for me.
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