Flowerpots as caves.

[Peter Stegenborg Larsen <psl@cs.auc.dk>]

I am going get a couple of dwarf cichlids, and I was wondering how
flowerpots is used as caves. 

Do I turn it up side down, and break a little of the rim, so the
cichlids can enter? 

Which size and type (material) of pot is the bedst?

Is it better to find rocks, and build the caves myself? And if so, do I
have to glue them together with silicone?

Thanks in advance
Peter.