AceJohnny2: thank you. Figuring out how to build standardized aquaponics systems that are self-stabilizing (e.g. by using inexpensive sensors and Raspberry-like computers to monitor and regulate all elements), and finding cost-effective ways to deal with the regulatory issues you mention, are the kinds of challenges that ambitious entrepreneurs must overcome to be successful.

The question I would ask at this early stage is really about the odds of finding product-market fit: if a startup can figure out how to make a standard, modular, legal, self-stabilizing aquaponics unit that is easy to install and maintain, is there a sizeable market for it? I suspect the answer is yes.