pH in both tanks has dropped to 6.0 or less overnight
KH has dropped to 3dKH overnight in tank without iron, cannot test tank with iron very well because of red color, but assume it is the same. I was able to make out the yellow color for the pH however. So both tanks have plummeted to acid conditions with the addition of the hydroponics fertilizer. So this is a game changer, yes? If this is not some kind of anomaly, then the fact that the ferts caused the lowered pH, will also mean that the EDTA iron WILL be available to the plants. (6.3 pH or below to utilize EDTA iron). It also means that it's a good thing I don't have fish in my tanks when I fertilize! Such a drop would surely kill or at least hurt them.
I really need to test this with the CSM ferts, and others meant for aquarium plants (Not hydroponic ferts like I use), but do not have those since I only fertilize outside of my tanks anyway...except for the leaf zone or Aqueon Plant food, which I will no longer use unless my tanks are at 6.3 or under pH.
Assuming that the CSM and other type aquarium ferts most often used by those with planted tanks do not cause such a drastic change in pH, there is still the issue of EDTA iron not being available to the plants unless in pH of 6.3 or under.
Last edited by AWolf; 04-10-2016 at 06:40 PM.