Re: Nutrient stability

John Y. Ching writes....

>I know that Dupla is a proponent of the daily Fe regime. How come other
>brands recommand weekly or bi-weekly Fe feeding with water change?
>How long do the nutrients remain available to my plants in the aquarium
>water anyway?

The half-life of FeEDTA is anywhere from three to ten days in an
circulating nutrient solution. Light levels affect its stability as
does pH. I'm guessing that other chelated metals are more stable than
FeEDTA, but this may be incorrect.