Did you have an ammonia spike? If so, its good to go. I don't know how many fish you can introduce at once, but CUC has no limit. Add what you want. I have a 90 gallon and added 10 nassarius snails, 4 hermit crabs, 3 peppermint shrimp, and a brittle star all at once. I started with 3 fish, and then added 3 more the next time. I wouldn't overload it with corals right off the bat. Give them some time to adjust and go slow with them. Some corals do better in longer established tanks and won't survive in a one or two month old tank.
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