In a couple of weeks my reef will will have reached 40 years old. Unfortunately I don't remember when I was 40 but I remember when I set it up. I was a skinny 22 year old just back from Viet Nam. It is still running very well, still using the same reverse UG filter, same dolomite substrait but none of the fish are original. The oldest one, a fireclown is just over 16, all of the older fish died in an accident that was due to my carelessness. The tank is mostly LPS, gorgonians, giant mushrooms and a few leathers. There are only three SPS corals, two of which have been with me for a few years and are growing nicely. I am not sure is any of the original NSW from the Long Island Sound is still in there or any of the original amphipods but maybe much later generations. I still can't take a decent picture and the tank is not as blue as these pictures but it is what it is.