I been looking for a centerpiece fish to put in my 60 gallon tank. I always wanted to put wild discus inside, but read that it has to be in a group. Can I only put one in the tank or do I have to have a group. My tank consist of pork chop rasbora, dwarf rainbows, and bunch of expensive plecos. If I can't put one discus, can someone tell me another fish I can get.