Hi all, I've seen someone with a freshwater tank use this media as a sand bed, I suppose the idea being that it doesn't compact like sand and at the same time provides bacterial colonisation surface area. TBH, I don't find it offensive, a lttle unusual perhaps, but the ultimate goal is to keep fish and corals right?
The only caveat might be whether or not it gives off silicates to the water.
To that end, I'll email Eheim and see what they say.