In my discussions with friends about the system I am building, one question I have been asked repeatedly is whether such a system is cost effective. Another way of asking whats the payback period for the system.
Now I am building my system from recycled parts myself, and I am not building it with the intention of reaching payback at some point in the future, but it is an interesting question none the less.
Written back in 2009, the paper was commission by a gentleman in Canberra looking to promote aquaponics locally. It takes into account the the captial cost, as well as the running costs, of a number of off the shelf systems sold by Backyard Aquaponics.
While I haven't verified the numbers myself, after reading the paper I believe it covers the majority of costs involved and provides a reasonable estimate. For those not wanting to read the full paper, the answer is 2 - 3 years (depending on the size of the system).
While your milage may vary depending on your system setup (as well as the changes to costs in 2011), it backs up my gut feeling based on my own estimates.