I am trying to find a good brand of sowing medium for a few phal seed pods I have growing. Anyone have any favorites?

Sorry, I seem to have broken the golden rule all too quickly. Please DO NOT respond to this with any brand names, since that is against forum policy. Perhaps though you can help me answer what ingredients make up a good medium? Charcoal, agar, banana? Does it need to have sucrose? Thanks...and sorry about asking for brand names!