I use gold and got some pretty good results. :))

I still fight the yellow houseplant fungus plague Im having, so I took a cutting of the kerrii and throw away the pot. I tried vermiculite this time, it has a funny metallic/golden color and can retain an amazing amount of water while still remaining light with a lot of air between the pieces. The cutting is maybe 2 weeks old, nicely callused and has small roots already.