I also use AE trace in my EI regime, dosed in the concentrations specified by AE. 1 tblsp trace to 500ml water and then 10ml of this solution per 100l tank water each dose, Sun, Mon, Wed, Fri
It contains the following elements:
Boron 1.06%
Copper 0.23%
Iron 8.2%
Manganese 1.82%
Molybdenum 0.15%
Zinc 1.16%
It will work out a lot cheaper for you as well.