hydriods is the big deal, that and anything else that might sting the ponies. Your sand and rock basically need to be "dry" when you start your system, or you can treat it with panacur. Once you treat the system, you probally will never be able to keep corals or inverts. The BBS can easily introduce hydriods. Plus you have to have almost no flow at all for the dwarfs---so that limits you even more!!!! I hate to refer you to another site, but have you looked at seahorse.org ??? they have a dwarf forum, read it---and when you are done read it again!! Dwarfs are alot harder than most people first think!!