Regarding fish: You have a 220G tank. What is with the tiny little timid fish?? Mostly joking. But you will likely switch to larger fish, and then the tiny ones will be lost or picked on. The firefish in particular are really timid. Pajama cardinals get big though. And oddly mean looking. No worries there. Basically: Really think long term when planning. You may want have a few tangs eventually. Although they would eat the non-calcareous plants. Perhaps some dwarf angels. But key is your choice on larger carnivores. If you want any. If you will add a big Wrasse or two, those tiny fish are not just picked on, they are lunch. You may also want some "dither" fish. A small school/shoal of active swimmers to keep the others happy. Chromis, Anthias, and few others.