I currently add 5 cubes of frozen mysis/plankton/spirulina to my 55-gallon tank: 3 cubes at ~11am and 2 cubes at ~7pm. I also sometimes put a sheet of algae in the tank for the fish to peck at. I currently have a 4.5-inch tang, a 4-inch wrasse, a 4-inch rabbitfish, a 3.5-inch clownfish, a 3 inch triggerfish, a 2-inch dottyback, a 1.5-inch royal gramma, a 1.5-inch mandarin, a 1.5-inch cardinalfish and a 1-inch clownfish. Oh, I also have a long engineer goby. I know that's a lot of fish for the size of my tank - but if I don't overfeed, maybe the bigger fish won't grow too big for the tank. Just wondering if I should increase or decrease the # of frozen cubes every day.