Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
I would approach this from the other direction.
1) How much dry fertilizer do you want to give the tank in one week? (what formula/kind of iron is it? Are there instructions with it? Can you look up instructions?)
2) How much liquid do you want to dose at any one time?
If you will be dosing every day, 6 days a week (and one day off for water change) and you can dose 8ml each time, then multiply 6 x 8 = 48 ml.
So, put the amount of iron you need for 1 week in a bottle.
Add 48 ml of water.
Dose daily @ 1ml per gallon.