I was wondering that myself. I just figured that they just put 2 different species together in a tank, and hope something happens.. but I was watching this thing on t.v., and it was about salmon. it was a local fish breeder and what he was doing, was raising a bunch of females, and then when it was time for the egg laying process, he would squeze out the eggs, what looked to be jus a big glass of water, and he would take sprem, and spray it all over the eggs. after I watched the show, I thought well can this be done with tropical fish as well. I don't see why not, the only thing I wonder, if you squeze the eggs out of the females belly will she die? and were the heck do you get all the sperm from, slaughtering the bunch of males? if that's the case, is it worth it, probably not to the fish, but to the new guy on the block, that's making $$$$$$$ why not there only fish, millions die everyday for the friday fish fry....
if anyone knows of the process, post it on here, I would like to read up on it ore.. there are alot of over seas breeders I think that are doing it this way.. where else do some of these fish come from...
andy