I am new to keeping fish other than feeders from Petco... I have a 29 gallon tank and I am planning on including live plants. Some of the species that I am looking into are platys, cory catfish, and maybe another schooling fish (cardinal tetras?). What are the minimum schooling sizes for these types of fish? Will the tank be overstocked? The tank has to be as peaceful as possible. I have been researching centerpiece fish and I don't know what the best options are. I would like something that is larger than the rest listed and with an attractive look. First and foremost, I need my fish to not harm each other. I've heard that gouramis, angels, bettas, and cichlids work as centerpiece fish; but many of those are notoriously aggressive. Any advice or experiences????