Quote Originally Posted by MarkS View Post
personally I like the coarse stuff, the section of plastic light diffuser (egg crate) can have a tendency to sink into the finer stuff but as long as it sitting on top and not sinking it should be fine.
I got a recommendation from Corey to use a couple of lengths of PVC on the bottom of the tubs to rest the diffuser on to keep it from doing just that.

While we're on the topic, water to substrate ratio won't be as important with this method, correct? As long as there's plenty of water in there to keep humidity up (but not dripping), I'm good, right?