My first marine fish tank?

the bigger the tank the better and the more you can keep in them! from my experience the marine fish need plenty of room, more than tropical and freshwater. Research on what fish get on together as fighting occurs a lot within the tank. clownfish was where i started they are hardy creature and make good first time owners. Snail and crabs are excellent for the tank as they clean it which means less effort on your part. sand is brilliant for the tank although it is difficult to clean it is better for marine to imitate there natural environment which means coral would also benefit from being in there as well as live rock as it circulates the natural chemical balance of the water which will only lead to a healthy fish tank plenty of hiding spaces should also be included especially when first induces a species as this reduces stress if they are away from prying eyes :) a heater, filter, and air pump is needed as well as salt and a hydrometer to measure the balance of salt in the water as it needs to be exact be warned that the salt content needs to monitored frequently as it changes. hope this helps!