[Z Man]

Sorry John but I don't want to burst your bubble but I ran a fishroom with 80 tanks and bred at different times well over 200 different species if fish. I never made one penny over my costs. I sold to one store that gave me one half of what he sold them for. They took all I could produce! The cost of electricity, water and mostly food far exceded what I got for the fish. I never needed any type of license and was never questioned about one. You have a long time ahead of yourself so just be careful on how involved you get when there is not that much of a return money-wise.
P.S. The hardest and most expensive part is raising the fry to a saleable size so you can get the most money for them. And this store has well over 400 display tanks & for the 10 years I did this, I'm not going to say how many I sold but you can take a good guess yourself. It was a LOT of fish.