Contaminated Fresh water supply
- dkoons16
- Scurvy Dog

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Contaminated Fresh water supply
Have a 1998 400 CMY, just purchased. The water tank after, I filled it, became clogged with black slime at the filter. Cleaned it and worked for about 5 minutes. (Water pressure motor was ON). Came back to boat next day and turned everything on again, ran for 10 seconds and stopped. All faucets.
I'm assuming its the filter again. I know how to clean the tank, but I need to empty it first. Any tips or suggestions would be appreciated.
Thanks in advance,
D & D
I'm assuming its the filter again. I know how to clean the tank, but I need to empty it first. Any tips or suggestions would be appreciated.
Thanks in advance,
D & D
- tomschauer
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Re: Contaminated Fresh water supply
I believe your tank is under the aft cabin bed. Open up the access port and use a larger pump without a filter or a shop vac to empty it and suck up the worst of the sludge.
- Midnightsun
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Re: Contaminated Fresh water supply
What he said, if it's like mine you will have a 4" diameter access port on top, suck everything out with a shop vac. Then rinse with a hose from the access port. I would then add some water and shock treat with bleach. Here is a picture of the access port on mine.


- dkoons16
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Re: Contaminated Fresh water supply
Thanks, I will try that. I'm also having issues with the system holding pressure. Hopefully its only the clogged filter.
- dkoons16
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Re: Contaminated Fresh water supply
Emptied tank and its in worse shape then expected. Has anyone replaced a tank? How difficult is it to do yourself?
- Midnightsun
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- tomschauer
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Re: Contaminated Fresh water supply
It depends on the access. If you can easily remove and replace it without removing all kinds of other things its pretty easy.
You have a fill line, vent line and outlet to the pump. Maybe a level sensor.
You have a fill line, vent line and outlet to the pump. Maybe a level sensor.
- dkoons16
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Re: Contaminated Fresh water supply
Midnightsun wrote:Qr Bbpost Is the tank plastic or aluminum?
Plastic tank
- bud37
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Re: Contaminated Fresh water supply
A plastic tank that is not leaking ??.....why not just clean it as has been suggested.....that will be much easier to clean than replace. Just need a shop vac and some brushes.
FWIW.....The above is just my opinion.
- Midnightsun
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Re: Contaminated Fresh water supply
A plastic tank is good forever. Just a good cleaning a some disinfecting with bleach and same as new. Just decommissioned mine last week as sit on the boat typing this drinking water from my tap. 
