[reeffantic]

I look forward to seeing how your rock experiements work out. Like you, I have a large tank and no money so I need to make my rock but cannot think of a way to both lighten the rocks and make them as porous as possible. It is to bad standard wax pieces is a no no. It would be easy to take shavings of wax, mix it with the cement and oyster shell, and after the rocks are solid, cook the wax out. I have heard of mixing paper pulp in the cement. I wonder how well that works and what the ramifications might be.