That is how Amel does their grey water. We have to be very careful on Kristy SM243 not to put any foodstuffs down the sink, but even so will get a funky smell from the bilge every few days even when we're not cooking...just from shower/sink drainage. I put a little bleach and a little soap in each of the sinks and run it into the bilge, let it sit a while, then pump it out using the whale pump that takes almost all of the water out (rather than the electric pump that leaves a good bit in the bilge). If I do that about twice a week I don't get any smell from the bilge, and I use the whale pump on a regular basis to keep it from drying out and make sure it works.
I'd be interested if anyone else has another solution to the grey water smells. I have thoroughly cleaned the bilge last Fall, but it didn't really change the odor issue.
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