Bad water in new boat

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Nordic Star

Veteran Member
Joined
Dec 24, 2016
Messages
63
Location
United States
Vessel Name
Nordic Star
Vessel Make
1969 Pilot House Trawler
Unfortunately I discovered the hard way the water in my recently purchased boat has some bacteria in it. I'm asking for solutions to fix this problem. She carries 150 gallons (2 75 gal tanks). I've heard Bleach (1/2 gallon in each tank?) or water purification tabs.

All suggestions are welcome!! Thanks.
 
Don't put that much bleach in!!! It only takes a little. Best to search on Google, try" how to disinfect marine water tanks "
 
look for peggie's posts but basically drain and flush the tank and all lines, then add bleach and run all lines until you smell bleach then let it sit for a few hours then drain and flush again, remembering all lines. I always added baking soda and did another drain and flush.

Don't forget the ice maker lines!!!!!
 
look for peggie's posts but basically drain and flush the tank and all lines, then add bleach and run all lines until you smell bleach then let it sit for a few hours then drain and flush again, remembering all lines. I always added baking soda and did another drain and flush.

Don't forget the ice maker lines!!!!!

And do it as many times as it takes. Then also look out for a recurrence.
 
Easy fix. As BV said, find Peggie Hall's posts on the topic, and flush using her recipe/method.

Once that's fixed...

FWIW, we use sequential filters when we fill our fresh water tanks. First is dual-gradient 25/1 micron, second is .5 micron filter similar to a carbon block drinking water filter. Part of that is a bit of over-kill (I'll remount the second directly on the galley faucet when I get a round tuit) but since we usually fill from a well-water source, it helps me keep the sediment levels down.

-Chris
 
I would also recommend after doing all this that you get the water tested. Make sure no bacteria remaining.
 
Id prefer to use a commercial product like "beer line cleaner" these type of cleaners descale tank bottoms and lines break down salts and proteins which cause smelly water and don't leave that chlorine smell.
 
look for peggie's posts but basically drain and flush the tank and all lines, then add bleach and run all lines until you smell bleach then let it sit for a few hours then drain and flush again, remembering all lines. I always added baking soda and did another drain and flush.

Don't forget the ice maker lines!!!!!

That's how it's done. Well, add bleach and then fill with water, then run until you smell chlorine at each outlet (hot and cold). Let it sit like this overnight, drain and flush with fresh water.

Use plain, ordinary bleach, not perfumed or "non splash" bleach. This is chlorine, the same chemical cities put in their water to sanitize it.


If you fill your tanks with a clean "drinking water only" white hose and use treated water, you should be OK in the future. If you have to fill them with untreated or questionable water, add a tablespoon of bleach or so for each 20 gallons.
 
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I first found these instructions for recommissioning the fresh water system in 1989. Today you can find them on just about every RV site on the net as well as in both my books:

The following recommendations conform to section 10.8 in the A-1 192 code covering electrical, plumbing, and heating of recreational vehicles. The solution is approved and recommended by competent health officials. It may be used in a new system a used one that has not been used for a period of time, or one that may have been contaminated.


Before beginning, turn off hot water heater at the breaker; do not turn it on again until the entire recommissioning is complete. Icemakers should be left running to allow cleaning out of the water feed line; however the first two buckets of ice—the bucket generated during recommissioning and the first bucketful afterward--should be discarded…bleach does absolutely nothing to improve the flavor of good Scotch!

1. Prepare a chlorine solution using one gallon of water and 1/4 cup (2 oz or 25 ml) Clorox or Purex household bleach (5% sodium Hypochlorite solution ). With tank empty, pour chlorine solution into tank. Use one gallon of solution for each 5 gallons of tank capacity. (Those are the “official” directions. They work out to 1 quart or litre of bleach/50 gallons of water tank capacity , which is MUCH easier to calculate!)

[FONT=&quot]2. Complete filling of tank with fresh water. Open each faucet and drain cock until air has been released and the entire system is filled. Do not turn off the pump; it must remain on to keep the system pressurized and the solution in the lines [/FONT]

[FONT=&quot]3. Allow to stand for at least three hours, but no longer than 24 hours.[/FONT]

[FONT=&quot]4 Drain through every faucet on the boat (and if you haven't done this in a while, it's a good idea to remove any diffusion screens from the faucets, because what's likely to come out will clog them). Fill the tank again with fresh water only, drain again through every faucet on the boat. [/FONT]

[FONT=&quot]5. To remove excess chlorine taste or odor which might remain, prepare a solution of one quart white vinegar to five gallons water and allow this solution to agitate in tank for several days by vessel motion. [/FONT]

[FONT=&quot]6. Drain tank again through every faucet, and flush the lines again by filing the tank 1/4-1/2 full and again flushing with potable water.[/FONT]
 
Bleach works as a function of both concentration and time. Dilute mixture will work if you give it a couple days of contact time.

My tank got stinky a few times and 1:1000 concentration did the trick over a couple days. With that low concentration you don't have to be that anal about how much flushing you do.
 
I first found these instructions for recommissioning the fresh water system in 1989. Today you can find them on just about every RV site on the net as well as in both my books:

The following recommendations conform to section 10.8 in the A-1 192 code covering electrical, plumbing, and heating of recreational vehicles. The solution is approved and recommended by competent health officials. It may be used in a new system a used one that has not been used for a period of time, or one that may have been contaminated.


Before beginning, turn off hot water heater at the breaker; do not turn it on again until the entire recommissioning is complete. Icemakers should be left running to allow cleaning out of the water feed line; however the first two buckets of ice—the bucket generated during recommissioning and the first bucketful afterward--should be discarded…bleach does absolutely nothing to improve the flavor of good Scotch!

1. Prepare a chlorine solution using one gallon of water and 1/4 cup (2 oz or 25 ml) Clorox or Purex household bleach (5% sodium Hypochlorite solution ). With tank empty, pour chlorine solution into tank. Use one gallon of solution for each 5 gallons of tank capacity. (Those are the “official” directions. They work out to 1 quart or litre of bleach/50 gallons of water tank capacity , which is MUCH easier to calculate!)

[FONT=&quot]2. Complete filling of tank with fresh water. Open each faucet and drain cock until air has been released and the entire system is filled. Do not turn off the pump; it must remain on to keep the system pressurized and the solution in the lines [/FONT]

[FONT=&quot]3. Allow to stand for at least three hours, but no longer than 24 hours.[/FONT]

[FONT=&quot]4 Drain through every faucet on the boat (and if you haven't done this in a while, it's a good idea to remove any diffusion screens from the faucets, because what's likely to come out will clog them). Fill the tank again with fresh water only, drain again through every faucet on the boat. [/FONT]

[FONT=&quot]5. To remove excess chlorine taste or odor which might remain, prepare a solution of one quart white vinegar to five gallons water and allow this solution to agitate in tank for several days by vessel motion. [/FONT]

[FONT=&quot]6. Drain tank again through every faucet, and flush the lines again by filing the tank 1/4-1/2 full and again flushing with potable water.[/FONT]


Peggy Im surprised you feel that just treating the water is enough ?? I have seen 1" of hard sediment in the bottom of a 1000 liter tank and water lines junked up with minerals and junk from hard water supply and no mater how often the water was treated with chlorine the rotten egg smell would eventually come back .
 
Just FYI, I had a persistent rotten egg smell with my fresh water. Bleach never would cure it. Finally tried hydrogen peroxide and that cleared it up. I think it was the hot water heater causing the smell, but it's gone now.
 
There is a difference between an adverse bacteria in a water tank (as the Original Post) would indicate and any and all smells one may be experiencing from the water. Bad smell does not necessarily indicate a bad bacteria. Nor does water that smells great indicate that there is not bad bacteria in it. Two different things entirely.
Peggy's formula works out to be over 50 ppm which is what is recommended for new municipal lines and tanks at 24 hrs. 2ppm is recommended as a maintenance concentration. They make a dpd chlorine test kit that is pretty reasonably priced from Hach test equipment. I am a customer but in no other way associated with Hach.
 
Cardude: If it was the water heater it was probably the sacrificial anodes in the water heater, fairly common.
 
I agree with Gaston, with a 48 year old boat you probably have inches of crud in the bottom of your tanks. The tanks on my 40 year old boat had about 4 inches of sludge in the bottom. Vacuumed the tanks and hosed to get sludge past the baffles, then filled and shocked with bleach per Peggy's instructions.
 
Cardude: If it was the water heater it was probably the sacrificial anodes in the water heater, fairly common.


Maybe so. I think you're the person who told me to try the hydrogen peroxide. Did that clean the anodes maybe?
 
Cardude, I may have. The anodes, just like the zincs on your boat are designed to disappear or sacrifice themselves prior to any corrosion of the tank and/or elements in the heater. It could also have been a different water source. Iron and Manganese can cause the smell also and those are found here and there and can be "seasonal" during spring and fall overturns of surface water sources. Both are naturally occurring and considered a "taste and odor " problem and not a health hazard. Hope all is well out west with you. Happy New Year.
 
Don`t overthink this. In our rural areas reliant on tank water from rainfall on roofs, it is said that if there is not a dead possum in the tank, the water lacks flavor.:eek:
 
The better (more expensive) water heaters have glass lined tanks and sacrificial anode rods. When the anodizing wears off the rod, replace the rod...a simple inexpensive cure for the "rotten egg" smell that's only in the hot water. Those water heaters have lifespans of 20+ years. Unfortunately though, the least expensive water heaters have anodized steel or aluminum tanks...and when the anodizing wears off anywhere, the only cure is a new water heater. Average lifespan can vary from about 5-10 years.
 
One caveat to all this is to NOT use chlorine if you have aluminum tanks! You will need another product as chlorine is very rude to AL.
 
Warning! I'm going to recommend a product that I sell so I may be biased.

It's called Puriclean made by Clean Tabs in the U.K. It will not only purify the water but will strip the biofilm that forms on the tank walls.

Practical Sailor did tests of water purification products. They liked Purisan for tank cleaning and Clean Tabs for water purification. Yes they liked it better than bleach. It is also safe to use in aluminum tanks.

Clean Tabs Ltd | Water Purification | Water Purification Tablets | Water Tank Cleaning | Water Treatment | Drinking Water Disinfection

Puriclean - MFG#UPCSTD - 14 oz. Tub
 
[FONT=&quot][FONT=&quot]Although most people think only in terms of the tank, the plumbing is actually the source of most foul water, because the molds, mildew, fungi and bacteria which cause it thrive in damp dark places, not under water, which is why it's im[FONT=&quot]port[FONT=&quot]a[/FONT]nt to [FONT=&quot]leave [/FONT][/FONT]the [FONT=&quot]water pump on to keep the system pressu[FONT=&quot]rized so that the solution remains in the lines.

[FONT=&quot]However, if there's s[FONT=&quot]cale, sludge or slime in the tank[FONT=&quot], by all means clean the tank. But don't stop t[FONT=&quot]here.[FONT=&quot] Re[/FONT]c[FONT=&quot]ommission the whole system. [/FONT][/FONT][/FONT][/FONT][/FONT]
[/FONT][/FONT] [/FONT]
People have expressed concern about using this method to recommission aluminum tanks. While bleach (chlorine) IS corrosive, its effects are cumulative. So the effect of an annual or semi-annual "shock treatment" is negligible compared to the cumulative effect of holding chlorinated city water in the tank for years. And it’s that cumulative effect that makes it a VERY bad idea to add a little bleach to each fill. Not only does it damage the system, but unless you add enough to make your water taste and smell like a laundry, it’s not enough to do any good. Even if it were, any “purifying” properties in chlorine evaporate within 24 hours, leaving behind only the corrosive properties.

[/FONT] [FONT=&quot]To keep the water system cleaner longer, USE your fresh water...keep water flowing through system. The molds, fungi, and bacteria only start to grow in hoses that aren't being used. So before filling the tank each time, always let the dock water run [/FONT][FONT=&quot][FONT=&quot]long enough to flush out all the water that's been standing in the dock supply lines (wash your boat first) so that what goes into your boat is coming straight from the water main, 'cuz [/FONT]the same critters that like the lines on your boat LOVE the dock supply line and your hose that sit in the warm sun, and you certainly don't want to transfer water that's been sitting in the dock supply line to your boat's system.
[/FONT]
 
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About chlorine I would advice not to use a too heavy dose as one of the side effect of running a highly chlorinated water in the whole circuit could be to deteriorate some seals here and there.
 
Just please don't judge clean by smell or even taste. Please test the water quality. Water might well pass your smell test and still be filled with bacteria.
 
Thanks All. My water does NOT smell but I can tell you it does have Bacteria :(. Not after this weekend though :).
 
Just please don't judge clean by smell or even taste. Please test the water quality. Water might well pass your smell test and still be filled with bacteria.

Which is the reason why no toilet designed to use raw (sea, lake, river) water should ever be connected to the potable water system.
 
Many good areas of advise above. I will add one of my tricks. I often keep my tanks chlorinated more than most would like to drink or use for cooking. I also use a Seagull filter for drinking and other potable water use. The filter extracts chlorine and bacteria. Belt and suspenders.
 
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