Paladrium for fire bellies

[Kinky kirky]

I'm soon to be starting my paladrium for European FBT's, still in the research stage and getting materials at the mo. I've got a 4ft, 300l fish tank I'm going to use with just under half being land. The water part is going to keep fish and I'm using my big external filter with the outlet on the land to create a stream/waterfall to keep the water lovely. I'm going to use rocks to make the land, but my question is what do I use as substrate? Whatever I use I'll have a moss layer on top and I want it planted. Any other tips on setting up or advice on the frogs would be great, thanks in advance.

[Kinky kirky]

No one?

[Tobiascole]

I used coconut fiber as my substrate. It worked out great.