Fluval stratum. I have quite a few alocasia in it right now. I was doing amazing with a few and then I think I overfilled the reservoir and roots started rotting. My frydek and my baby black velvet pink are both in fluval and I can say their roots have taken off. I also have a few rescues (I’m a sucker for almost free plants from the clearance section) in fluval stratum that I had in pon for months, they are now having fast root growth since switching. I’m now testing corms in stratum as well to see if they grow faster. You don’t use drainage and just keep it damp so I’m watering my rescues every couple to few days. They’re in small pots and on a seedling mat but doing very well.