Determining NFT:Media Bed size ratio

[Tony L]

Does anyone have info on how many more plants a media bed can sustain versus how many it can physically hold, assuming the standard 12" depth?  I'm planning a 112 plant NFT system and am trying to size a media bed that will have a bacterial colony large enough for both the NFT and media bed plants.

I understand the basic concepts and am not asking for the commonly cited material, I know how to figure out how much fish food I need to sustain 112 plants.   I want to know what is the smallest size media bed possible to support a 112 NFT system without using additional biofilters.  Thank you.