Whatever you decide to breed, make sure you develop a good relationship with one or two lfs before you start.
Research your market.
Find out what sells, even if they don't sell for a lot of money. There is no point in you dedicating time and money to breed something that no-one will take off your hands.
I just wandered around my lfs and, over a period of a few weeks, I could see what stock was moving out of their tanks, and what WASN'T selling.
As has been previously stated, you will probably never make a profit, but you will be able to use the cash generated to offset your expenses. Most stores I know will give you 1/2 retail value of your fish for STORE CREDIT, but only 1/3 retail for CASH.
Go for the store credit. That's why it's important to develop a relationship with the store first. Then you and the staff can get to know each other, they can advise you on the type of fish they would be willing to buy of you, and for what price.
I've currently got an lfs taking Convicts off me for £2 a pop store credit, and 2 different stores waiting on my Platies getting big enough, then I'm looking at 75p a pop for them. So far my fish have paid for their own food and some equipment for my tanks. It's fun to go into a store and walk out with stuff without any cash changing hands!
It's fun breeding your fish, and the fry respond to you as they grow - they know where the food comes from!
Heres a few of pics of my tanks - one with my breeding Convicts, another with my fry/growout tanks. This is strictly small scale, and I've recently changed the top tank in the "stack" to a 20 tall, but hope it gives you some ideas....
Good luck with it....
