Water System Mayhem !

[harmony80]

Been having the same problem this summer and we flushed the tanks, cleaned filters, added vinegar, and we are carrying less water and flushing hoses frequently. The problem seems to have gone away. And we are also filtering our water before filling the tank and we filter at the galley. We also bought all new water hoses. And FYI, when I began the process, our filters clogged immediately with those white crystals...no more chlorine for my tanks!

[GordMay]

Originally Posted by svHyLyte

... for the first time we have a definate "rotten egg" smell in the water that flushing only defeats for a short while.
Thoughts?

The rotten egg smell is likely Hydrogen Sulfide (H2S), possibly from your Hot Water Tank.
Often, anaerobic bacteria that exist in some water, and react with the magnesium and/or aluminum sacrificial anodes that come with most water heaters, to produce hydrogen sulfide gas (H2S), making the classic rotten egg odour.
Using a hydrogen peroxide solution of 4 ounces of 3% peroxide to 5 gallons of water, treat tank and run some of the solution into water lines.
Let peroxide solution set in tank and pipes for 2 hours. Solution is not toxic and requires no rinsing.
Then replace anode with a zinc-alloy anode.

Sulfur dioxide, on the other hand, is a heavy, colourless, poisonous gas with a pungent, irritating odour familiar as the smell of a just-struck match.

[ronh732]

As a water treatment plant operator, I would suggest opening everything up and giving everything a good scrub, inside hoses, lines, pipes, tanks everything, replace things you can clean inside. Even though a strong dose of chlorine (>10ppm) should kill everything, if the build up of biological material is thick enough some will always survive and you will be back in the same situation in no time. Yes its a painful difficult process but once it's done you should be able to prevent a re-occurrence with regular disinfection and bi annual shock treatment.
With an aluminium tank I would suggest switching between disinfectants on a regular basis as well as monitoring the pH of the water in your tank. Most disinfectants are corrosive and adjusting the pH with lime or soda ash can increase the life of your tank. You can easily adjust the pH and still maintain a effective chlorine residual of 0.5ppm. Vinegar will be neutralised by pH adjustment. Hydrogen peroxide is an effective agent for rinsing tanks and lines (once the slime is physically removed).

The rotten egg smell is typically hydrogen sulphide and/or sulphur dioxide produced as a waste product of iron eating bacteria and is a common problem in water that is high in iron and manganese and in wells with iron/steel pipe casings. On board a cruising yacht you may have iron or steel fittings somewhere in your system that are corroding and the bacteria have gained a foot hold that protects some of them from the disinfectant you are using. Again you need to find the source and physically remove it in order to prevent re occurrence of the problem .
Hope this helps

[sarafina]

Originally Posted by foggysail

GEEZ GORD,

ONE major mistake in 19,000 posts? No apology needed!!!

too true!

retraction much appreciated, however. ; -)

[svHyLyte]

Originally Posted by GordMay

The rotten egg smell is likely Hydrogen Sulfide (H2S), possibly from your Hot Water Tank.
Often, anaerobic bacteria that exist in some water, and react with the magnesium and/or aluminum sacrificial anodes that come with most water heaters, to produce hydrogen sulfide gas (H2S), making the classic rotten egg odour.
Using a hydrogen peroxide solution of 4 ounces of 3% peroxide to 5 gallons of water, treat tank and run some of the solution into water lines.
Let peroxide solution set in tank and pipes for 2 hours. Solution is not toxic and requires no rinsing.
Then replace anode with a zinc-alloy anode.

Sulfur dioxide, on the other hand, is a heavy, colourless, poisonous gas with a pungent, irritating odour familiar as the smell of a just-struck match.

Gordo et al--Thanks for the notes/advice. Please note that we changed the annode in our hot water heater and thoroghly cleaned same about 2-1/2 years ago (see http://www.cruisersforum.com/forums/...ter-21275.html ). The stench is evident in all lines and fixtures including a fixture in the galley that is connected to a foot pump that only draws water directly from the tanks well before the hot water heater.

I shall flush the tanks again and try the hydrogen peroxide. This does or does not need to be flushed out? You say above "Solution is not toxic and requires no rinsing." so I'm not clear on that.

Thanx...

[zeehag]

hydrogen peroxide breaks down rapidly into water and oxygen.
non toxic.

[sdowney717]

I have bendable copper water pipes with bronze fittings.
Stainless 75 gallon water tank
no iron anywhere
I do unfortunately have an aluminum hot water tank which is in good shape with a magnesium anode.

So far no issues with water contamination. The marina has well water and I dont put it in the boat, I bring water from home to fill the tank.

The biggest weakness is the aluminum tank for water. IMO, not a good choice to use aluminum for water. There is a possible link between Alzheimer and aluminum.

[zeehag]

the most immediate problem with water heaters is the leaking at the corners of the square tanks. comes along looong before alzheimers will ever set in.
is why i took mine out and and threw them away.