Bunnings mate, has everything you need. You can grab blocks of coco peat there for about 10 bucks. I used a mixture of washed forest sand, vermulite (I think that's how you spell it), moss peat, coco peat and organic potting mix. And then put a layer of spaghnum moss ontop, making sure there's no fertilizer and its all organic. It's all down the one isle, I work there part time lol.
If you go the live substrate way, you will need to put either a false bottom in or have very good drainage ie. The gravel you have at the moment, under the soil. This is needed to stop root rot on the plants and stopping it from smelling funky after awhile as well as breeding harmful bacteria.
My frogs always go live plants over the fake ones in my viv, and they look great.
Hope that helped :-)
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