So I have been attempting to start a micro aquaponics system in my backyard for about a year now. I've gotten the basics up and running with the system however I still seem to be missing some fundamental aspect of how these systems work, as I am and to get growth out of my crop but their growth seems to be stunted about half way through the growing process.
I have found out that until your system has reached that mature stage testing the water to key. Several times I have discovered that my ph in the water has risen to over 8 which was the cause of my plants being locked out of their nutrients. So now I have been testing regularly every week and my plants have been improving.
Moral of the story test your levels regularly