You really don`t need that much now and tbh theirs no need to go over 3ml a ltr which is for first 3 weeks of 12/12 before dropping back to 2 to 2.5ml per ltr after 3 weeks. Adding more ferts dont mean more bud it usually means a whole heap of problems later on down the line as plants slow down on uptake and ferts build around roots.
If its pk13/14 boost your using its harsh stuff so keep eye out on plants leaves, i mean i tend to use 1/2ml per ltr of that.