I bought a plant fertilizer named FERTI PILL #6.  It is a 6 gram tablets with 
the following guaranteed analysis.

Total Nitrogen (N) *			14.0%
	4.6% Soluble
	9.4% Insoluble
Available Phosphoric Acid (K2P5)	4.0%
Soluble Potash (K2O)			6.0%
Calcium (Ca)				3.0%
Sulfur (S) combined			3.0%
Iron (Fe)				0.5%
Derived from: Ureaformaldehyde, Calcium Phosphates, Potassium Sulfate, Ferrous 

* 12% Slowly Available Nitrogen from Ureaformaldehyde.

I want to know, if this would be a good plant fertilizer to place in the 
substrate of my tank?