55 gallon, soft water, 50/50 and Actinic lighting, New World Cichlids ......OR......33 gal x-high Marine tank with 110 watt power compact lighting; Prizm protein skimmer; powerhead; 300 watt heater.
Be patient. Be patient. Be patient.
New World Cichlids.
What is that smell?
I've been keeping aquariums for 25 years. I have kept 10 gal; 15 gal; 20 gal high; 33 gal x-high minireef; 55 gal and 67 gal tanks.
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.