feeders are good boosters for making your fish grow fast... i learned my lesson when i fed my datnoids with feeders and they all got sick. i'm lucky enought to have no casualties. now i only buy feeders from wes (rare fish) and i don't quarantine them to be fed to my 6 growing bichirs.. never had any problems. but precaution would be better.. usually drop a fungus clear on them and they should be good.
