Water Drain Depth

[arachdog]

Hi,

And what do you think might replace it?

Well I'm no soothsayer Gary. Nor am I actively involved in the field. But it makes sense to me, that techniques that have proven to be more efficient in producing plant growth, even if they do require more management will rise to the surface. So if I had to guess NFT since that has such a good track record, then ultimately perhaps aeroponics, though its probably going to be a while before that become economically viable.

The reason that it has the most research behind is because it was the system that worked. Dr James Rakocy tried grow beds 25 years ago and rejected them for commercial purposes.

Well 25 years is a long time. Its a different world, its probably worth another look

In my view, (and aside from anything else), NFT is too fiddly when compared to raft.
NFT has also been around for a very long time now. Dr Allen Cooper developed it in the mid 1960's if I recall correctly.
Actually, most of the NFT troughs that I've encountered have been white. The root zone issue has more to do with the relatively small nutrient flows being exposed to high ambient temperatures. Cooling towers and other strategies have been employed to counteract the problem.

If the ambient temperature is too high for the roots then wouldn't they be too high for the plant as well ? In any case it's either not a problem in all climates, or its an entirely solvable or at least manageable, as proved by its wide spread use in hydroponics.

Raft is much simpler to put together and more stable because of the much greater volume of water.

I agree but as is often the case your trading off performance for reliability.