Working full time for more years than I want to admit to paid for the equipment I started breeding with. Used 20 gallon tanks for $12, 10's for $4. First spawn of 200 angels, at $1 each, paid me back, with some left over. The left over got rolled into more tanks & gear.
Do this enough times, and everything is paid for, the fish buy their own food, cover their own utilities, and leave some extra money for me to play with.
I'm surprised younger folks don't breed more, easy money if you have no job. I could double what I put out of my fishroom if I didn't have to work. Problem is it would have to be somewhere around five times to match what I make working full time.