actually I discovered rice hulls by accident because I live in a rice growing area and a friend of mine gets them free by the truck load .We started using them for mulch outside and one day while looking for madium to repot phals in and not finding any available in a store local I just repotted one into rice hulls ....worked so well for me I started using them for all the phals and experimented untill I figured out that after they sit outside in a pile and weather a season they work great .....fresh just harvested ones are actually to dry at first and need lots of regular watering and are so loose the phlas will fall right out of them ....after a season outside in a bucket with holes in the bottome they are perfect hold just the right amount of water and actually can be watered almost exactly like any house plant in siol would other than the fact that the water will drain out so fast you need to do so in the sink....I usually have a saucer under them so it holds water and lets it wick up and from there it really is something that will depend on your conditions in the room.
If its a very very dry room "and the room these are in is with wood heat " once or twice a week without a saucer of water under them ...with a saucer pretty much when the water is gone but pay attention to how moist they are just like soil if it seems dry give them a drink if they are staying a little to wet dont leave quite as much in the saucer ....
Pretty simple here is a linik to a picture of one in rice hulls
http://www.orchidboard.com/community...-phal-now.html
and a few other phals in rice hulls as well
http://www.orchidboard.com/community...f-georges.html
they do pretty good in them and these are at a friends house who is not good with orchids ...lol I used to go once a week and water and check on them ...have been way to busy to the last year and they dont look as good this winter but they are all alive and spiking even with major neglect and dry most of the time....
---------- Post added at 12:33 PM ---------- Previous post was at 12:32 PM ----------
oh and pure rice hulls alone