[VeeSe]

I have some iron that I got from GLA. I don't remember if it was EDTA or DPTA but their page today says 11% DPTA, so if they haven't changed it, then that's what it is. I've heard (don't remember from where) that this only lasts a few hours in the tank. If I dose this 12-15 hours before the lights come on (just after lights out), is it just useless?

 

[Wasserpest]

You mean Iron DTPA, correct? It has a stronger bond than other chelators like gluconate and EDTA, so it should last longer. How long exactly is probably hard to tell, depends on pH and other things, but monitoring your plants should be sufficient. If they show iron deficiencies like Chlorosis, then you would need to increase either amount or frequency of fertilizing.

 

[VeeSe]

My lights turn on daily at 1PM and I'm at work for the whole day, so there's no way I can dose it shortly before lights go on. I haven't noticed chlorosis but I haven't exactly been looking out for it either. It sucks that I would have to change my lighting schedule in order to dose iron into the tank, as changing it to a 9AM-5PM schedule would effectively mean that I see my tank with the lights on for 0 minutes on 5 out of 7 days of the week.

 

[Wasserpest]

Why do you feel it is important to dose iron just before lights on, or at a specific time of the day? Plants don't stop assimilating nutrients just because it is dark. I think you are overthinking this :smile: I doubt you will see big differences whether you add the ferts before, after or during the light period.

 

[VeeSe]

Why do you feel it is important to dose iron just before lights on, or at a specific time of the day? Plants don't stop assimilating nutrients just because it is dark. I think you are overthinking this :smile: I doubt you will see big differences whether you add the ferts before, after or during the light period.

Oh, I thought that they primarily uptake nutrients during photosynthesizing periods.

 

[plantbrain]

Without uptake, 2-3 days typically, but is dependent on the KH.