How much iron per gallon per week?

[Stan510]

Really,iron is pretty much all the plant additive you really need. Potassium distant second. Foods=fish poop and local water have enough of the rest.
So I found some company that says hydroponic plants need about a tablespoon per 10 gallons once a week. How does that sound? Too much for aquariums? What do you think?

 

[Colin_T]

you want 1mg/l (1ppm) or iron in the water, no more. What that works out to from a dose rate could be anything depending on the original product you are using. You will need to add a small amount and monitor the iron (Fe) level in the aquarium water. If it is too low, add a bit more, wait a few hours and check again.