thanks Tom and Daniel, I've read through the old postings right now and understand how complex the Fe chemistry in water is. In the past I have added macros and trace on a daily basis altogether the same time without issues. But will start dosing trace/Fe in the morning and NO3/PO4 in the evening to see what will happen. Regarding the fast uptake rate for Fe and the duration until Fe disappeares from the water body about 12 hrs difference (morning to evening) should be sufficient to separate the nutrients from each other I suppose. Further more I will do some testing to see the interferences between PO4 and Fe if there are any at all.
I don't think it matters so much but dosing every other day with alternating macro/traces vs 3x a week is easier for many.
A consistent easier to tremember routine is what6 many find "better" and why folks that test often, provided their tesat kits actually work, do "better".
Anything you tend more often, you take more consistent care of the planted tank, that's often the real issue at play rather than the routine itself.