Oops sorry forgot to add that. I'm thinking of starting with a silver and then a black. Although I've very recently grown alot on the gold which I can not find pricing on anywhere! :/ I bet they're expensive though. Any advice?
Silvers are common and easy to find. Blacks are all wild caught and rather expensive. Tangled up in Cichlids a vendor here on MFK has 12" blacks available. You could wait until spring and possibly find some baby blacks to raise. They are a challenge to raise from babies but a very rewarding experience.
As far as Gold, if you are refering to asian arowana, they are illegal in the USA.
The isn't really such a thing as a "high quality silver", not like with the asian species where different farms put a lot of effort into breeding the best possible strains. Your options are either wild caught or captive bred, and usually they're not specified. IMO blacks are pretty much the closest you'll get to a high quality silver (no DE!) so you could just go with that...