Probably my biggest orchid discovery in the past two years is the ability of chunky perlite to open up a medium and keep it open through the lifecycle of its accompanying media. I add it to bark and sphagnum and I find it really helps prevent overwatering, especially as the other media break down over time. Quality is key and i didn't have a good source for a long time, but this stuff is great and a good price (I'm not affiliated). Just thought I'd share, strongly recommend.
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