A new farm in Mendon just installed some new footing that is a waxed sand (and heaven only knows what else) and supposedly never needs to be dragged or watered. They’ve only been up and running a few months so there is probably no way of determining if it really doesn’t need water or dragging. You could contact them to find out what they use and where they got their footing.
http://overthemoonfarms.com/
I used mason sand in my indoor 24 yrs ago and added rubber from Footings Unlimited about 8 yrs later. My footing is still good but it’s never had hard use over the years with usually only 1 or 2 horses per day in the winter months.