Feed Conversion Ratios
Another advantage of aquaponics that I failed to mention in the original post is the feed conversion ratio of fish as compared to other livestock. Unless your “backyard” is large enough to produce free-range/grass fed livestock or you can grow and process your own feed, your going to need to purchase livestock feed. Below is a comparison of the feed conversion ratios for various livestock:
Thus we can see that fish are much more efficient at turning feed into body weight than other forms of livestock. Whether or not this inherit efficiency translates to reduced feed costs is beyond my ability to calculate at this point. I suspect the cost difference between feeding laying chickens and feeding fish would be significant, but I’m really only “guestimating”.
One more tidbit, fish waste contains no e-coli pathogens, so contamination of the produce is not a problem.