[hongrui]

i've tried pine bark and charcoal and coco husk. i find that pine bark works pretty well as an additive to open up the media. i've not observed much of a difference in growth between 1:1 peat: perlite compared to 1:1:1 peat: perlite: pine bark for most neps. the only nep that i grow and that it likes a fair bit of bark in the mix is N. veitchii. the epiphytical nature of the N. veitchii suggests that it should like a fair bit of bark in its media.