Hello Nick...I'm sure this thought of turning a hobby into a business has crossed interest with many on board here. You're guaranteed to receive mixed feeling on whether to go for it or not.
First as a hobbyist you need to make a name for yourself without negative reviews. I've heard many say you need a fortune to make a fortune. You will need a regular clientele to turnover your stock to pay the bills. Even with a small scale operation I feel the supply and demand locally may not cut it.
I don't want to discourage you in any way but at the same time if your going to sink funds into this business you will need really-really research this one out.
Here is a thread you can read through that may offer an answer... http://forum.simplydiscus.com/showth...=fish+business
...Ralph