You do realize that you're going to have to give us your address so that we can see this thing next time we're driving through...
If you could build the tank sturdy enough, I'd like to see a hydraulic jack that hoisted 1 end up and down an inch or two, so that you could get a back and forth surge thing going on.
Or maybe an inside baffle that raised and lowered and accomplished the same thing.
(Save some money on circulation plumbing... lol )
Mitch
(I'm joking, btw, on the hydraulic jack...)