Allan there is an organic radio host, Howard Garrett, who does a 4 hour seg Sunday mornings plus one hour Q & A on Saturdays. He's wildly popular in Texas. I've seen photos of his home and his greenhouse is a knock out. He insulates the walls with 55 gallon barrels of water. It just looks like a prime set up to incorporate household fish tanks as an offshoot from one of them he could aerate, recycle the water into his plant growing system and have some 'free protein' for his family as well. I was thinking tilapia would do well in something like this. (they may be considered a pest fish, can't have them in a pond or open water source.) I don't have any idea what 'organically grown' greenhouse fish would require though. Cornmeal, boiled egg, mealworms plus algae?
My biggest drawback is my husband, can't toss too many new ideas at him at once.