Barry Rice has a short article that's worth reading:
http://www.sarracenia.com/faq/faq3330.html

Here is a link that might be useful: Charcoal & Nepenthes

Thanks...I guess that answers that. I was intending to use a mix of long-fiber sphagnum, perlite (as close as I can get to volcanic rock) and sand. Maybe a bit of orchid bark in the bottom of the pot to keep the holes from plugging up....

Cheers

I recommend not using sand, as it does not drain well, nor does it provide good soil aeration, both of which are fairly essential for root growth, and if you ever plan to fertilize through the roots, which I recommend, the sand will prevent drainage and will lead to salt build up which will lead to death of the plants.

If you plan to use a fertilizing regime, use a media which will dry out between watering. I like pumice (not perlite), orchid bark and cedar mulch (un-dyed type)
Mix this evenly and fill pots that are not over sized. Use a pot that has lots and lots of drain holes. Mesh pots are also great for this plant.
Other media used includes coco bark (use sparingly), chopped osmunda, and lesser amounts of LFS.

Fertize again, RainforestGuy?

How grows it in Hawaii?

Even if rainforstGuy lives in Hawaii, I live in Utah (a desert) and doing what he said is the only way to get mine to grow good.