My dreams are already so crushed you can put them in a mesh bag and use them for bio-media!
I learned fish breeding from the proverbial old man with a tiny shop. The money isn't in the fish, unless you go into the high end of the market. At least in my local market, the money is in dry goods - filters, tanks, gadgets, test kits, foods, lights - but not fish, which most stores hope will break even. If you breed fish, you need more gear. You sell the fish to the shop, and you get goods in return. They mark up your fish five or ten times, and they've already marked up the goods.
To be honest, I have had had a lot of store people suggest how I could breed a certain fish, but they usually don't know because they have no reason to. They mean well.
They just want to sell me things I might not really need, so that sure isn't limited to the fish world. Everyone tries to sell me useless objects.
It takes a lot of capital to run an aquarium store now. The outlay is really steep. A good friend is opening an aquarium section in already successful pet business, and I certainly wouldn't be able to lay out that kind of start up money. When I was 20 I thought I'd retire and be the old man giving advice in a small shop, but small shops are a thing of the past.
Still, a person can dream....