Highly concentrated (10,000 mg/L) ferrous iron gluconate supplement
It should be used in those cases where the iron requirements exceed that which can be delivered by Flourish™ at the recommended dose or signs of iron deficiency appear
(such as short and slender stems or yellowing between veins.) Contains no phosphate or nitrate
Seachem - Flourish Iron
Plants are able to much more easily derive a benefit from Flourish Iron™ than from EDTA-iron sources because all EDTA iron is in the ferric (Fe+3) state.
Since plants require iron in the ferrous (Fe+2) state, additional physiological energy must be expended in order to extract the ferric iron from EDTA-iron and then convert it to the ferrous form.