Carol - Something to consider about using S/H culture in very dry environments, particularly when it comes to phals:
Phalaenopsis, for the most part, are "hot" growers, never seeing temperatures below about 70-75F, and frequently seeing triple-digits. Fortunately, for us, they are reasonably tolerant of the somewhat lower temperatures we prefer, making them pretty good house plants.
Now, fast-forward to winter. It's cold and dry, the ambient humidity is low, so when we heat our homes, it plummets. Looking at the inner workings of a semi-hydro pot, we see a very open and airy medium, with lots of surface area, and lots of moisture spread around due to the good wicking. Ideal for evaporation, which brings evaporative cooling along with it.
If, like many, you lower the household thermostats at night to save on energy, then the evaporative cooling, enhanced by the low relative humidity, can lower the temperature of the root zone well below the plants' acceptable range, and that can lead to root death.
There are ways to combat that: raise the humidity to decrease that cooling effect, or raise the pot temperature by putting them on heat mats.