foam drainage layer

[evilhorde]

Rockwool is often used as a growing meduim in hydroponics as well, so I would presume that it would work well. I have never actually held a piece in my hands so I can't speak for it's drainage ability or longevity from personal experience.

[Flemish]

Greetings.
- I would not trust it to drain fast enough, as the LECA does...
But it block and hold back water, it will absorb though. But it will not give its water away, and soil will be flooded instead.
Flemming.