While I prefer a serious looking reef, I really think my students would love a gimmicky shape of encrusting coral that our Cyphastrea meteor shower (origin: @wpeterson ) can grow over. Inspiration: While I do not want a skull, I saw this online and it is the right idea. Or maybe small ones that could live in our frag tank. I think I saw on this club website a Homer Simpson Chia pet, also the right idea. ???What materials would be safe???