As much as I like my zeo products I don't think they are the be all and end all. I noticed that at one stage I was doubling my start 3 dosing , that had little effect on the tanks water quality. (rescued my tank with a different brand product)
Zeovit - teaches the aquarist about routine on the otherside I found my tank looking best with little more than a weekly water change.
One thing to remember is that tanks go through phases in maturation, what worked best upto three months may not work after twelve months. Adapting dosing to the tanks maturation, sometimes dosing less frequently can be key to success.