A quarantine tank is a separate, smaller fish tank that is used to segregate brand new or sick fish. Many people claim that a quarantine tank is a MUST have for any aquarium, and the reality is, you do. No one wins in the long run without having a quarantine tank, some just have better luck for longer than...
For someone new to the marine aquarist hobby, I’d recommend no less than:
Aquarium
Stand or place to put the aquarium
Cover
Light
Heater
Thermometer
Hydrometer (or preferably a refractometer)
Mechanical filter
Skimmer
Equipment to make up fresh saltwater from mix
Quarantine tank and appropriate...