I've looked and can't find the answers to this: 1) I know angels need tall tanks rather than short, but how tall is tall? Will they do okay in a 16 inch tall (30 gallon long) tank? 2) Can you keep an angel alone? If you have a pair, does it have to be a breeding pair, or does gender matter? 3) I think they are compatible with guppies and cories. I don't plan on keeping my danios, so that's not a concern. Are they compatible with neon tetras? I've read mixed things about this, wondering if anyone has an opinion. What about cardinal tetras? And black mollies? 4) Do you add them last to the tank, or does it matter? My tank has 6 cories and 3 male guppies. I am thinking 8 small tetras, and/or possibly 3 black mollies. For a centerpiece fish, I've been thinking of a dwarf or honey gourami, or maybe an angel (or two)... any opinions? edit: the angel/neon question was answered in a thread by redlessi, thanks.