Welcome to AA! Some of those fish need about twice the size of your tank. Don't recommend box fish either b/c when stressed or when they die they release a chemical that can kill all your fish! Also the lion fish will eat the clowns and dragonet if it has an opportunity. It's hard to have a predator tank w/ a 75. Maybe the lion, an eel, a trigger, and/or possibly a puffer? That might be too much and I don't know a whole bunch about predator tanks. However, they are messy eaters so factor that in when choosing. Lastly, dragonets are very picky eaters mainly eating copepods. They can eat 2,000+ a day b/c they just eat all day. It would be better to buy a mandarin that is already trained to eat frozen food, but wouldn't recommend one in a predator tank.
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