Sonic plumbing for everyone
 

I got sick of the water tank venting on my sub woofer when full, and the dash cooler draining into the bilge, so I fixed them. I have the drain and the vent going into a "t" then to the galley sink drain. Remove the fridge and its all easily accessible. Mine gurgles because I ran it along the floor with the original fresh water lines, but if you drilled a new hole into the galley cupboard, I think you could avoid the noise. I don't mind because I don't run the water often.

Yeah I kinda wondered why they did that, run the cooler drain to the bilge, instead of a t-fiting right to the sink drain going out the side. Mine was the same way and I changed it.

Although my water tank vent went out the side of the boat exaclty like the gas vent is.

I have never seen those kinds of mufflers, good to know though.