[GpsFrontier]

I don't doubt the STG product works well, provided the user understands it's property's (as with any growing media). But I have never really considered using the STG product due to it's relativity high cost. It has similar proprieties to rockwool, but don't think it wicks up water as much (so it's supposed to help aerate the roots better). And it always seems to cost much more than rockwool. And I don't even like using rockwool for anything other than seedlings, mostly because it cost too much. So I just don't even buy rockwool, unless it's the 1 inch starter cubes.

P.S.
It's hard to tell from the video, but those NFT channels are quite shallow, and from the top I don't see any baskets or clips holding the growing media up. So to me it looks like the the STG cubes are sitting directly on the bottom of the NFT channels in the stream of water where they get moisture 24/7. That would indicate they surly don't wick up water the way rockwool does, or they would be waterlogged. That's just what I mean by understanding the properties of the growing media your using, and using a growing media that suites your needed. Or adjusting your system to accommodate the properties of the growing media.