Low to zero input, Aquaponics

We are building an urban farm in Los Angeles CA.  
Our goal is an Aquaponic garden that not only raises fish and vegetables but the food for tilapia.  
By mimicking intensive grazing techniques for cattle our tanks are long and narrow with fencing gates that will allow Filamentous algae to grow and be grazed as we open the gates.
This will feed our mature tilapia. For the fry and fingerlings we are collecting mud from local wild rivers to seed small water fleas and whatnot for protein sources.
Has anyone else had success with these types of approaches?        

The only people I know that have great success with the model you propose, use ponds to raise the fish instead of tanks.
I am sure it will work as long as you really think through every possible thing that could go wrong, of course you will find more once you set up, that is farming and aquaponics is fish farming.

Redhawk

Algae can get out of hand quickly and take over everything sun shining on. I would opt for duck weed and azolla for tilapia food and try to keep the water quality at the top so that the taste of the fish is better.