Food for predator fish

[WesternSpyKolya]

So yesterday I got 1 popeye sea goblin and 1 dwarf zebra lionfish. I'm thinking of feeding them mollies since they eat live foods (currently) but as I wean them to frozen food what would be adequate to feed them? I know foods high in thiaminase can lead to an early death so I'm avoiding them as much as possible but could anyone with prior experience help me?