Probably mysis shrimp which would be the natural diet for most reef fish. I suppose you could raise them just as they do rotifers. You need to feed them the appropriate micro aglea/plankton to sustain them.
Congrats on good animal husbandry practices. Tanks are full of neat suprises, eh?
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Currently tankless.
20 Gallon mini reef with mated pair of Maroon Clowns given to Rougiem!
80 gallon reef given to Rougiem/Wooster HS.