If you don't like flake (and I don't) there are two excellent alternatives and we feed both but they are expensive. If I only fed the tanks one food it would be frozen Cyclop-eeze. The second that we include in our daily feeding is small frozen mysis. Both will be happily eaten by your fish and any form of serpent and we have seen the octos take at least the Cyclop-eeze (and likely the mysis). I have a video of my post hatch female (Trapper) mercatoris directly eating it from a pipette. Other evidence of the octos eating it is circumstantial (color of their poop) and it may be they eat the pods that we also know consume it. Our clowns love the combination and the softies can eat both as well.