Sludge buster?

[rinker1]

For what is worth, I flush about 1 lb of ice down the head. Flush about a hand full of ice at a time. I do this on a nearly empty tank. I then take the boat out and shake things up. The loosen everything up on the bottom of the tank. At the pump out dock I fill the tank full of frsh water and then pump it out. It really works well.

 

[Vic Willman]

Andy, I've heard of people doing that before, and they all say it works very well. If you have a removable cleanout cap on top of the tank, that's another place where you can add the ice, instead of pumping it in through the toilet. Some guys don't even bother pumping it out right away, they just let it melt, and wait until the next pumpout.