Can anyone tell me where a good reference point is for the science for aquaponics. I need to understand the things that I HAVE to esnure. I was just thinking that if I had the reasons behind something then I can understand why I need to do something - hope that makes a little bit of sense !!. Some of the following questions I need to answer :

Do the beds need to be underwater (or at least mostly) ? If so why ?
Am I right in thinking that the volume of the beds needs to match the volume of the water for the fish
How mush of the water do I need to turn over every hour / day ?
What can I add if there are not enough nutrients in the water for the plants to grow ?
Were can I find a detailed design that is already proven.

Sorry for all of the questions !