I'm starting the process of planning a new stocking for my 20 gallon standard and I need some advice. The tank is currently at a pH of 8.4, temp of 78* (heated), 0 amm, 0 nitrite, 10 nitrate. It is lightly planted with a black substrate, seashells, and a fake driftwood/log thing. The filter is an AquaClear 50 rated at 200 GPH. It is currently housing 8 neon tetras (to be moved to a different tank) and a ton of MTS. For starters, I'm thinking about moving my 6 male blackbar endlers and 3 panda corys into the 20 gal and upping the cory school to 4 or 5. Would that be an appropriate number of corys in this tank? Now for the yet-to-be-determined tankmates... Could I do either a German Blue Ram or Bolivian Ram as a centerpiece fish? Or do they need to be in pairs and if so, could I have a pair in this size tank? If those are not an option, what would be a good colorful centerpiece fish? For reference, I love the GBRs (obviously), flame gouramis, and cockatoo cichlids. Actually.... could I do one male cockatoo cichlid with my endlers and corys and maybe something else? Or maybe even an Angel fish? As for schools, I definitely want to keep my endlers. I like the cardinal and neon tetras but I don't want any of them in this tank, as I already have some in another. I like the looks of some of the longfinned tetras (like the black skirts) and ember tetras. I would also like to have some shrimp in the tank, if possible. So what do you guys suggest?