In this country, it cannot be labelled as a fertilizer unless it has at least one of those three nutrients, and with the concentrations of each specified in the proper order. This creates a problem for trace element mixes, as here they cannot be legally labelled as "fertlizer", even though they are - they have to be labelled as "supplements".
In emerse growth, the best ratio may be different from that given for submerse growth. I've only grown Anubias emerse using a waterfall into a veggie filter tank, such that it was getting sprayed with tank water constantly - no additions beyond those already in the water were used.