Thanks, Seachem, for your response. I have been dosing iron and flourish on the same day, every day. The precipitate is a distinct rust color, not the white cloudiness one might expect from the iron.
It wouldn't surprise me that I'm overdosing iron. I have no confidence in iron tests, however, so I rely on the eyeball method.
Using trial and error, if I back off the iron until I see early signs of chlorosis will I have an accurate read of my iron levels or will plant vitallity drop off before that point?
As noted earlier, I'm heavily dosing Flourish in addition to the iron. I know that Flourish has some iron. Is it possible that I don't need to add supplemental iron? Does my dosage level of Flourish sound reasonable to you?
My tank is heavily planted, high tech, CO2, MH lighting, etc. My tap water is from my well and has little in it except liquid rock.