Hi, welcome to the board. First we need to know what filtration you have(filters, protein skimmers). Here would be a nice setup for you.
4 in. Male blue jaw triggerfish, a dwarf (zebra or fuzzy)Lionfish, and a eel(snowflake would be excellent).
If your thinkin why a male, for a blue jaw trigger, i'll tell you. Both of these fish are extremely hardy, pretty nice (for triggers), eat almost everthing, but males arew BEAUTIFUL. they are a light blue, with a dark blue jaw. They are a lot though,around 50 bucks. The females are dark green, with a dark blue jaw. These fish are the same things in hardiness but are different in colors. Now since this triggerfish gets 9 in. You will need a 75 gallon or larger tank. Like I stated before this fish eats almost everything. You can give them frozen mysis, brine, krill, squid, other meaty foods, and flake can be offered. Don't give your trigger only one type of food, you should give it a variety of foods.
Dwarf zebra lionfish are the smallest lionfish there is, they get around 7 in. and need a 60 gallon or larger tank. This fish will eat the food I listed for the trigger, but no flake. If you purchase this fish, it probibly won't eat frozen right away. It'll eat only live food(guppies). When this fish is in your tank, you should try to wean it from live to frozen. Live is not healthy for your fish, it is full of fat, also it is bad for your fish's liver.
Snowflake eels are excellent eels, they don't get big, around 30 in.(30 gallon tank or larger) they love frozen foods, and may eat inverts. When feeding this eel, you should put it on a feeder stick, and feed it. Because when it is feeding on the top, it increases the chance of it jumping out of the tank. And if you get this eel, do not have any open spaces at the top of your tank. It will jump out and die. That happened to my friends eel, it wasn't good. Good Luck!