I have a four year old giant danio that i cycled my very first tank with. I know that doesnt sound impressive but what shes been through its amazing shes alive. I had a fifty five gallon tank of maybe thirty fish that were doing good until I got ick. I treated them with ick medicine and didnt see much results so i kept treating them and treating them not following the directions. I lost all the fish except for the four giant danios. I had the four for maybe two and half years then one died and within a week two more had died. But for some reason the one lived on and i still have her today. shes with four other giants but they are from when the other three died.