Breeder reef tank
Try, try, and try again.
Manderin gobi, ie. the psycadelic one. Marine beta, tru and false percs, and a few others
too many to count. some akens, LPS, SPS, and softies.
A man who carries a cat by the tail learns something he can learn in no other way.
In the hobby for about 8yrs now, kept all sorts of things great and small but reefs are the best.
When you see signs of stress in your fish, you can then take steps to identify the source of that stress and then to resolve it before it becomes a major issue.
If you're looking for a unique way to stock your new tank, give freshwater shrimp a try.
If your fish is suffering, you may want to consider euthanasia as an option to humanely end his pain.