semi-hydro questions still remain
I've googled and youtubed a lot about semi-hydro method of growing houseplants, but some questions still remain.
1. One of the disadvantages of semi-hydro is the need for relatively frequent watering. I grow inside where it's dry in the winter with humidity at ~35% or even lower sometimes. Considering trying some hoyas in semi-hydro (either rooting cuttings or growing or both) - they do not like soggy feet but most should not dry out completely either. How often will I likely need to water?
2. My medium for most plants right now is the gritty mix by Al in Container Gardening forum. He says (and it makes sense to me) that it is already very close to semi-hydro method: very chunky and superb drainage, can't really over-water no matter how hard you try. But there is no standing water at the bottom - instead the mix itself retains some water for the roots to use until next watering, just like regular pots, only with much more air. How does semi-hydro growing compare to gritty mix? Am I likely to see any improvement at all or is "perfect the enemy of the good" here? Has anyone done experiments for gritty mix vs semi-hydro? (controlling for the other factors, of course).
3. How come roots do not rot in that bottom inch of standing water? If they do not grow in there, what's stopping them? Can they be water roots rather than soil roots? How is THAT possible - they have to start as soil roots because they start in soil up above. Can a root become "water root" half-way down its length? Major confusion here.
4. I have not seen opinions on how different s-h media differ from one another other that to say things like "I like Hydroton more than Growstone" without really saying why. I would think that because Growstone has more flat(ish) surfaces, the wicking action will be better than with hydroton because there is more surface contact between the particles. Growstone also has more visible pores, so water retention also looks better than smoother looking Hydroton (although it has micro-pores, I understand). Apart from this general understanding of physics here, I do not really know what I am talking about, so would appreciate opinions on this. What is your favorite s-h medium and why?
Finally, 5. Just generally, what kinds of plants /growers /environments is semi-hydro better than gritty mix or 511 mix (another one of Al's mixes I use, generally for more moisture-loving plants)?