There was a lively debate on this at my OS meeting. Most folks said they kill phals in spag, and 1 guy says it has worked MUCH better for him than bark...and he grows 200+ phals, so he is hard to argue with . He says he "found the keys"...on one of his travels he went to a large overseas phal grower & learned that they 1) Pack the spag in very tightly, and 2) leave an inch of headroom at the top. When they water they fill up that inch, and let it slowly absorb into the spag. Then, that's it until they are close to drying out (but don't let it actually dry out). That and they told him to be sure and use long-fibered New Zealand spag, not the more readily available shorter fibered stuff. He swears his now grow like weeds, and bloom well (and the samples I have seen would bear that claim out).

I pass this along only FYI. I grow mine in bark, as I am a bit of a heavy waterer.