I got a YouTube spam for a product called Mapito Grow Medium. After checking it out it is my opinion the product would clog. It's made of Rockwool and shredded polyurethane flakes. I refused to spend $6.00 to get a first hand look, but from this description which I had to persistently dig for. I would think it might be good in Hydroponics, or Bioponics, but from my experience using various forms of media, it would not provide sufficient space for the debris of an AP system.
Hope this saves you the time I spent getting the information about the size of what they call PU.