I just re-discovered the Vengers Water Culture site (I had seen it a long
time ago, and I think that's where I got the idea that orchids must grow a
new set of roots to thrive in water?)

http://www.vengers.com/culture/water.htm

Anyway now I am wondering about "water culture" versus semi-hydro. Is
semi-hydro an improved version of water culture? How do they compare /
differ? If I understand correctly the vengers water culture site suggests
growing orchids just in water without any clay pallets or anything like
that. And then the algae growth is considered really beneficial in water
culture, but I don't see it in the semi-hydro basics
(http://www.firstrays.com/hydro.htm) from what I have read so far. But I
would like to know more.

Is anyone still growing in water culture? (The vengers site seems to be from
the 1990s, and I have not seen people refer to "water culture" recently, so
I ask.)

Joanna