[strath76]

I have used vermiculite on all species without any problems. It doesn't last as long as perlite and I have found that the drainage/aeration of the potting mix isn't quite as good. It also breaks down in the mix faster so will lead to repotting more often.

As for coco peat it should not be used for most CP's as it generally contains salt that leads to the death of most CP's. Nep's tend to be more salt tolerant than other species but still don't like a lot of salt.