Ice in Black Tanks?

While I don't believe that ice has any value at all, the video you see with the clear tank in the bed of a pickup is not a good indication of whether the ice works or not. It good video, just worthless. Look at how much water is in the tank....wait, don't look, that's how he gets paid.....let me explain. There is so little liquid in the tank that any benefit the ice might offer while in the tank is defeated by the lack of liquid. More ice and more liquid would have a completely different result but that's not the point of the video. Tests require testing. That means multiple scenarios and the results. I am also skeptical about what the solids in the tank are and if they relate at all to the solids in our tanks.
In the end (get it!) what you need is lots of water when you flush. Use enough, don't drain until the tank fills up and use a tank flusher from time to time and you should never need a bad of ice or anything else (including the Geo Method) in your black tank.