I have already done a search here. Too much iron isn't good. I have no correct means to measure the iron level. Am I dosing too much iron if I only add 1ml of it to a 40g tank with normal EI dosing? BTW, I mixed my iron solution in a 500ml of water and 2 table spoons of chelated iron. Other sources of iron are coming from my GH booster with Seachem equilibrium and the laterites in my dirt. I added a lot of laterites too. In the past, I used to dose iron 3x per week. Then, I stopped dosing iron for 2 weeks in order to see if my s repens would improve. Is hard to say since they are doing ok, not great, even they have been in my tank for over 2 months. They aren't thriving. I am thinking about adding iron back but with reduce dosage. Let says 1ml per each water change. I do 2 wc per week.