the reason that i asked for the dilution factor is if there were any published information on the minimum levels of nitrates to be able to maintain aquaponics, since nitrates can be measured, the type of plant and quantity would not need to be known. nitrates are insideous as far as the health and growth of the fish is concerned, because the fish's gills are not destroyed immediately as with ammonia, people are not as concerned as they should be with the levels of nitrates. fish weakened by nitrates are much more prone to parasitic infestations.