Sewage smell
- Thread starter Gary Ryan
- Start date
It's odor from your holding tank, escaping via the tank vent. Where is the vent thru-hull located--in transom or on the hull? What, if any, tank product are you using?
--Peggie
--Peggie
My solution would be to pump out and flush your tank with several rinses of fresh water at a pump-out station. At each rinse, let the pump's suction continue for a minute or so after the tank has emptied as the outside air is sucked though the vent and into the tank. This aeration should help kill off the anaerobic bacteria that is producing the odor plus remove the foul-smelling gas that is in there. When finished, put in maybe a quart or two of fresh water adding a proportional amount of treatment, a nitrate-based one such as Odorlos. Then, pump and rinse the tank after every trip or weekend at the slip. Don't regularly leave waste in there for more than a few days at a time. Pump regularly, full or not, but add additional treatment as tank fills with use, etc.
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Thoroughly flushing out the tank is a good idea, but first I'd make certain that the vent isn't even partially blocked. Then I'd just flush the recommended dose of a product called No-Flex Digestor Noflex Digestor which not only prevents odor from occurring in the tank, even in poorly vented tanks, but also prevents sludge. Add more according to directions.
There's really no need to pump out until the tank is full unless you're using a tank product that can't work if there's limited ventilation via the tank vent, which is highly likely if the vent thru-hull is in the transom.
And btw...Odorlos is a good product--it used to be one of only two products I recommended...but requires a new dose immediately after pumpout, again immediately upon return to the boat if you pump out last thing before going home, and at least every five days that you're aboard (being away from the boat longer than that prob'ly accounts for your recommendation to pump out so often). No-Flex has only been available for a few years and "knocks the socks off" every other tank product.
--Peggie
There's really no need to pump out until the tank is full unless you're using a tank product that can't work if there's limited ventilation via the tank vent, which is highly likely if the vent thru-hull is in the transom.
And btw...Odorlos is a good product--it used to be one of only two products I recommended...but requires a new dose immediately after pumpout, again immediately upon return to the boat if you pump out last thing before going home, and at least every five days that you're aboard (being away from the boat longer than that prob'ly accounts for your recommendation to pump out so often). No-Flex has only been available for a few years and "knocks the socks off" every other tank product.
--Peggie
Great ideas! I do add some product to the tank that I get from West Marine. Can't remember the name of it. I'll look into Noflex Digestor. Sure is great having a forum of people that don't mind helping out us newbies. Again..thanks for all the responses!
If that's where it is, you can improve the air exchange by replacing the "vent" thru-hull with an open bulkhead (aka "mushroom") thru-hull. That will also allow you to prevent any vent blockages by putting a hose nozzle against it and back flushing the vent line every time you wash the boat and/or pump out.
--Peggie
--Peggie