Hi Sharon,
The S/H media is little clay pellots that have been baked at a very high temperatue that makes them porous. They are a media that does not break down like bark or sphag, so the plants can stay in the same pot for many years without root problems caused by rotting media. I like that you can use recycled plastic drink cups for pots. A local bakery/sandwich shop sells tea in a clear plastic quart size cup. Perfect for an S/H pot! For semi/hydroponice to work, the cup needs a water reservoir in the bottom, so the drain hole is placed about 1 inch up the side of the cup. I usually cut a 1/2 by 1/4 inch slot for drainage. A couple of round holes will work just as well. The clay pellots wick water up from the reservoir to the area of the orchid roots, but the space between the rounded pellots provides plenty of air for those roots. Best of both worlds for them, air and water available at all times. And with the clear plastic cup, you can see the roots! Entertainment built right in!