I wish they didn't sell packs like that. The coral banded might eat your peppermints or they'll hide all the time so they aren't eaten. 10 ceriths should be fine but a Queen Conch shouldn't be in a 30g. And yikes that is an awful lot of hermits for a 30g as well. Unfortunately expect some die offs from some of that crew, it is unlikely there is enough to sustain them.