how do you know they will be fine after squeezing the cube out? What if there hungry? What if the ph is to high? What if nute solution is off? What if the cube is to cold/warm? It's not likely that the cube being to wet is his problem. He said they have good drainage and you would be hard pressed to over water rockwool on corrugated roofing, it holds so much air you need to either have it sitting in a pool of warm water or constantly be feeding oxygen depleted water to have those problems. It's likely a combination of things going on. Personally I would address them all and be done with it
Shouldn't squeeze rockwool either, you'll break down the fibers and it won't hold as much air. Set them on paper towel if you wanna wick out some water
Shouldn't squeeze rockwool either, you'll break down the fibers and it won't hold as much air. Set them on paper towel if you wanna wick out some water