Ok I need to say that although I Class myself as a newbie by today's specs I did dabble in marine about 40 yrs ago when I lived in Holland. It was non existent in the UK but big new hobby over there. No Internet, no Google, no test kits, just books and trust in the LFS. A hobby in its infancy, no sump, a skimmer and all the stuff in the main tank and a pressurised canister filter beneath. Usual size 3ft x 2ft x 2ft. Metal halide lights... no blue light led stuff in those days. I will say although I lost fish in the learning process and there were no corals to speak of, living rock was a must, but I managed to keep a YT, regal, powder blue, flame angel, Korean angel, bicolour, sweetips, a large anemome with hosting Clowns and believe it or not a pair of seahorses, a clam, shrimps, urchins and plus others I cannot remember. In those days there were no expert knowledge, a case of put it in and see what happens. Some with great success, I even moved them all to Germany and couple of years later and to the UK before the cost of running the 2 metal halides did me in. I don't remember the fish that survived the full experience or outgrew the 3ft tank, I also don't remember which passed away from the stress from it all but I do remember the YT stayed with me till the end. I remember finding a tiny crab inside a shell from Bournemouth beach when I got home so I threw it in the tank. Not to be seen again until it appeared from nowhere some weeks later about 3inches in size. It was so funny but it was removed. I lost interest at that point with the constant moving of army life.