I have decided that aquaponics is just kinda dumbed down bioremediation. That is sad, because I'm a huge fan of aquaponics, but the truth is too plain to see. Why would someone make a two-cell system that requires constant fish feed inputs when they can design a system that feeds the fish by itself? Aquaponics people have been thinking for a while about raising their own fish food, I must admit. Two great ideas proposed by Murray Hallam include Black Soldier Fly larvae:
Murray Hallam Black Soldier Fly larva (YouTube)
The company that made his BioPod is found here:
ProtaCulture

Hallam has also proposed duckweed:
Murray Hallam's duckweed

These are great ideas, and the studies on how good these two system elements are at converting waste products into protein and lipids are superb arguments for their inclusion in aquaponic systems. Sadly they are elements extraneous to the system as neither is directly integrated into the system. Black soldier fly and duckweed are considered supplements rather than food, and the main food given to fish in these systems is commercial fish feed. A large component of this fish feed is antarctic krill, which is being overharvested. In the final analysis, aquaponics is still an unsustainable system unless it can phase out fish feed. Given that black soldier fly larvae have a similar if not better nutritional profile than most fish feed, and duckweed and other vegetables can pick up the slack in other nutrients, it's a wonder why these elements aren't made integral to the aquaponics system.