Can anyone explain what happens to iron after dosing in freshwater aquarium? Both Seachem and Aquarium Coop say that it is utilized rapidly. What exactly does that mean? Seachem says to test within 30 minutes of dosing. I have a hard time believing the majority of water in the aquarium is exposed to plants and roots for the plants to strip iron from water in such a short time. Does some of it precipitate out or otherwise become unavailable to plants? If this is the case, Is it still harmful to fish/inverts if overdosed? Love learning about this stuff. Thanks in advance