I also use EcoEarth coconut fiber. I buy the ones in bricks, and add just enough water to break it all up. It holds the humidity really well, especially at first, but my CHE dries it out rather quickly (I'm also in a less-than-ideal glass tank). I will be experimenting with a layer of coarser coconut husk on top to see if it helps prevent it from drying out as fast. I like how soft the coconut fiber is, because it seems more like dirt. I didn't like how pointy the cypress mulch seemed to be when I first tried it.