1200x450x450 display tank
100 ltr sump
aqua one 2x150 watt metal halide
octopus DNW 200 skimmer
2 x 45s.nanos.
search the web for all the info you can get.research,research and research some more.
3 x blue/green chromis
1 green mandarin(male)
1 canary blennie
1 yellow tailed damsel
2 x banded coral shrimp(mated pair)
green star polyps
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.