Hi 15 gallon tank 2 fluval 10-30 gallon filters and one pulsating power head lighting is current loop I use no protein skimmer and no mechanical or chemical filtration I use a commercial brand of natural sea water and I change 2 gallons a week. I feed my tank pe. Mysis shrimp in the evening once an hour over 3 hours daily and I do not add anything else. I like to think of my tank as an updated eng style tank.