Neighbor put up an indoor horse arena. The floor is a mix of sand and shredded rubber laid down on top of a compacted limestone base. The dust is something awful, so he waters it, but the moisture takes the sand to the bottom of the mix and compacts it on top of the limestone so it stays damp and the top surface stays dry, which creates more dust. He was going to get a harrow to stir up that damp base of sand and get it mixed back in with the rubber pellets. I suggested a rototiller might work better. He's got a decent sized tractor, so he can pull just about anything. The arena is about 170'x80'. Any thoughts?