Hi,
The can't "target feed" a filter feeder Mysis shrimp. If your tank is squeaky clean, and you must feed the coral: Get a gizmo like sea squirt, and go just up-flow from the coral and release the food for to flow over it...get Kents marine microvert, or other food for filter feeders. Be careful, what feeds coral, also feeds nuisance algae.
Kole tangs will eat some types of macroalgae, so you can either purchase a not so tasty species, or set up a refugium. Hermits eat and kill your snails, I personally would opt for a variety of different snails to do a good clean up job and not keep hermits. However that's your personal choice....hermit crabs will not bother corals.
You need flow over the rocks to keep them clear of debris, the little bit of natural die off (marine snow) is what your filter feeder eats. The wave of the ocean brings the food to the coral, so ideally you what to duplicate that.
I run carbon to prevent coral chemical warfare. All corals will have some aggression, that's how they survive, but running carbon will ensure you have no problems.
