Krill and live crabs would be great food for a trigger, also I heard about feeder snails from one of the puffer links here:
topic137240.html. Have you thought of a Humu(humunukunukuapua'a) trigger or a Niger trigger? They get big but not so big as a Clown I don't think, plus they're pretty in their own way and don't cost crazy $$$. There are some LFS's that would gladly take a large Clown trigger (if it's healthy) off your hands for free (if it's healthy) and give it to a good home (for free, if it's healthy)! You would have to call around though and give advance notice for something like that.
I think your tank setup would work, it sounds like you're going for essentially a FOWLR with macroalgae, and a trigger would do fine there, along with other large fishes like an eel (snowflake, wolf or jeweled; chain and zebra get too large, garden if you can find it is near impossible to keep alive and also gets too long), maybe a full-sized wrasse (minimum 7" adult size), and even a tang. I would not get my heart set on any invertebrates whatsoever, as they will all become trigger food.
Also, I should point out that you sound awfully new to the hobby, so I'm going to give you a few tips that you didn't even ask for 'cause I'm nice:
1. Let your live rock marinate (i.e. cure) with your setup for a minimum of 2 full weeks (4 weeks would be even better!), with many water changes during that time to let the ammonia cycle. If you don't know yet what an ammonia cycle is, PLEASE ask here or do some research on this site to find out because it will save you many head/heartaches down the road.
2. Try to introduce your least aggressive fish (in other words, not the trigger) first. Try to make sure also that all of the fish you introduce are about the same size to start out.
3. Make sure you have a sealed top for your tank! Eels and wrasses LOOOOOVE to jump out to their own untimely deaths. It's a strange instinct, but it is definitely something hardwired into them.
4. Do as much reading as you can, here and in books about the hobby. Sure it's not as fun as actually buying the fish and looking at them, but it's a TON more fun than wondering why everything in your tank is slowly dying.
5. Be patient (kind of ties in with step 1). Setup takes a while, but so does acclimation, and growth, and just about everything else to do with this hobby. If you're not going to take some time and get it right, you are probably about to make a big (expensive) mistake.
i just want to know what size i should give it back to the pet shop? and is it coral safe?? im thinkin of a quite weedy marine tank with a sandy, rocky bottom and a bit of back work of LR. and any other suitable tankmates?? eels, flounders,cleanerfish? ect?????
