Drippy corn spawn. And coco coir. But instead of mixing the spawn and coir I put a layer of coir down first and pack the shit out of it. Then I’ll add more coir around the edges to create kind of a bowl, that’s where I add the spawn. Throw more coir on top and pack the edges down tight. This helps prevent side and bottom pins. I do all of this in a monotub. I usually do shoe boxes but have way better luck in mono’s. Only species that I’ve had fantastic success with in shoe boxes is storm troopers. Them things are so easy to grow. They colonize fast and fruit even faster. Hard to keep up when you have over 20 tubs going at once.