be careful with that shit man it really bumps your ppm through the roof... My honest advice to you is bag the HG all together and go with Canna nutrients. Canna truly is the better line imo.. that being said if your using your HG my reccomendation would be to use it twice and only twice, like the chart suggests. I used 2/3 dosage of the FIRST dose both times. In other words where it calls for one sachet the first feed i use 2/3 a sachet on both. Run your base nutes a little lighter too or not at all. Also, i would advise to always, especially with powerful solubles like Shooting Powder, to start with a low dose and slowly as time and a few crops pass you will learn what your plant wants and when it wants it. It really depends on your genetics, some plants suck nutes up at a record pace while others need very little feeding. If you post back about your system, strain etc i may be able to lend some more advice.
Also, a little tip, whenever your giving your plant a REAL concentrated or powerful nutrient or additive its always good to just barely wet the soil in advance with plain PHd water so you dont fry the dry root hairs with powerful nutrients. TRUST ME ON THIS ONE... say you feed a plant 500ml of water per container, first give it 25ml plain water to wet the root hairs. holler back