What are you growing?
Quite a bit, see the list below. The plant growth has been great and I don't really notice any significant deficiencies.
Rotala, Italian Val, Ludwigia, Java Fern, Amazon Sword, Anubias, Crypt W.
If your light is strong, then you might need co2 to increase growth and stop algae.
I'm aware, I assumed that Excel on an auto-doser would be enough but I am second guessing this now. CO2 is in the pipeline.
Why r you only dosing N and not P&K.
I don't have any experience dosing P&K, I'm not sure how to measure it. I'm hesitant to move over to a full EI schedule without CO2
Also if your using tap water, most of the time you don't need a separate Iron product or the trace the comp should be good.
My plants showed Iron deficiencies even with the root tabs. Since I started dosing iron they have gone away. This is why I dose even with tap water.