I couldn't get hydopon easily here, so I have been growing in lava rock. I'm finding that it works very well and is much cheaper. It also won't roll away If a pot gets knocked over. I have heard that the drawback is that the minerals will build up more, but if it is flush often, that shouldn't be a problem. It may need to be changed a little sooner.
Perlite floats too easily and would make it hard to keep plants in place.

Thanks for the info on long-term perlite, Ray, I'll keep that in mind as I try to rehab my new Phals.

The only OB member I've seen talking about using rice husks as potting medium is johnblagg, though I don't recall him saying he used it for s/h (not saying he didn't, just that I haven't seen it). Rice husks seem like they'd break down pretty fast with constant moisture, personally I'd stick with inorganic media for s/h.

--Nat

I agree. The whole idea is that they are growing in something that can't rot.

Rice Hulls are NOT good for semi-hydro! They decompose.