Basically everything!
They love live foods, but they shouldn't be offered much because live foods, are fatty, can cause liver problems in the future, and may carry disease. But live can be offered time to time for a treat. I use frozen foods, soaked in vitamin enrichers (zoe), which boosts up the fish's immune system. They like (frozen) squid, krill, mysis, brine(like what you stated), mussel, and basically all other saltwater frozen foods. Dry foods can be used, but aren't as nutritous as frozen. Any more questions ask (especially triggerfish questions.
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