Thank you Richard,
Empire gudgeons have been raised a few times up here in Queensland by putting the fry outside into ponds so that at least some of them could get the microscopic foods needed by the tiny fry.
A few serious breeders have raised them in aquaria by using the finest size of micro-encapsulated aquaculture food(i.e.APR= artificial plankton rotifer = Frippak). A few years back I corresponded with a breeder in Denmark (Jan Rottwit) who raised some fry
by feeding pulverised FW mussels (a blender job, I think) that has been strained through a very fine cloth.
BTW have you seen the article on Empire Gudgeons on Adrian Tappin's Home page. It can be accessed by linkage to ANGFA's Home page or direct.
Bruce Hansen ANGFA
http://www.ecn.net.au/~atappin/home.htm