Decontaminating water tanks

[VIEXILE]

Two years on the hard. Fuel got left on, engine dripped oil, some fuel into the bilge when winterized by the yard, didn''t turn fuel off, drip, drip. Bilge filled with rain water, snowmelt, into fresh water tanks. Skim of fuel and oil. How do I decontaminate the water tank?

[mrb2222]

Here is what I do.
1. Fill tank then drain it. Remove any filter you may have.
2. Pour in hydrogen peroxide - I use one teaspoon/gallon of tank capacity.
3. Refill tank and let sit a day. Be sure to pump this water into all lines before sitting.
4. Drain and refill twice. Replace filter if you have one. I use an inline charcoal filter from Lowes.
You''re ready to go. One exception is if you have a lot of algae built up then you may have to pull hoses and clean them. I clean the hoses by pulling soaked cotton balls on strings (Hydr Perox) through each line until clean. Do this after step one if you need to do it at all.
Also, I winterize my tank with the same stuff plus non-toxic anti-freeze.
Mike

[ABullard]

StarBright makes an excellent water tank cleaner that I have used with very good results. It has a foaming action that picks up contaminants not only in the tank but the water lines as well.

I used this product two years ago and the water, which had been really smelly, is now very good in taste and smell.

It comes in a gallon container. I had to use 1 1/2 gallons to clean three tanks holding 180 gallons of water.

Tony

[VIEXILE]

Thing is, we''re talking a diesel film in the tanks. There''s nothing in the lines YET, so I''ll pump straight from the tank until I get good water. Hydrogen peroxide, huh? Sounds good. I''m thinking maybe several flushes, some bicarbonate of soda, pressure wash, etc. I haven''t been near the boat in 2 years and am going to visit it next week. Sounds grim. I think I''ll do the Starbrite thing as well. Hard to kill diesel smell. Thanks. KW

[lauralee]

Ok How about this one. I get a sulferous smell from the fresh water holding tank. It has been like that since I bought the boat. What causes that? Any ideas on how to freshen up so I don''t have to smell that when washing up?

[GordMay]

From your post, I''m not sure how the diesel got into the water tanks, but I suspect it will be VERY difficult to get them potable clean & fresh .
Hence, suggest you begin trying with the cheapest alternatives first, which would include hand-scrubbing, if you''ve got inspection port(s).

OMO
Gord

[VIEXILE]

Actually, I assume there''s diesel in only the bilge tank, the saving grace. Ya. I''m figuring on a long-handled scrub brush, a pressure washer, bicarb of soda, peroxide, starbrite maybe AFTER a scrub and rinse with dish soap. Bilge filled with water sitting on hard, diesel dripped, filmed the bilge water and, I''m assuming, drifted into the empty water tank where I''d left the inspection port one thread down. Dumb. Forward tank is high and dry though, with 70 gals.

[RichH]

Probability is that a distinct species of bacteria growing in the tank is giving up the sulphur (and H2S) when the dead cells decompose. Get inside the tank and scrub off all the bacterial slime from the walls and tank top, Shock sanitize the whole system with a heavy dose of Chlorox, replace all polymer componets (including vent hose) that have turned BLACK. When clean maintain tank hygiene by adding Chlorox to the amount that is "barely perceptable" with you nose at the outlet.

Take a large wad of sterile gauze and tape it over the end of the VENT hose to prevent reinfection of mold spores, etc. Change yearly and keep dry.

[sailingbauble]

This won''t help with your present problem but it''s a good way to avoid a repeat.

When I have the boat hauled for the winter, I remove the speedlog transducer from its thru-hull mount in the bilge and leave the opening unplugged. This way, if water does find its way aboard, it can accumulate only until the level reaches the open thru-hull which is considerably below the cabin sole. Any excess drains harmlessly.

I imagine it also helps a bit with ventilation via the fresh air that is admitted.

In my case (Catalina 30), there is enough slack cable on the transducer that I can place it in one of the galley sinks where it will be in plain sight as a reminder to replace it before spring launch.

[VIEXILE]

NOW you tell me. But now that I think about it, there''s nothing lower than the water tank as far as through hulls go. Would''ve saved the cabin sole from getting diesel-filmed. We''ll see by friday how bad it is. Some say it''s o.k., others that it''s a mess. I''ve got to travel several thousand miles to find out for myself. KW