Got ya, would be interested to know what @osage and @chris_barfield have to say about this. Instructions on the bottle recommend 2mL per liter which equates to 7.58mL per gallon, that said I know it is not advisable to use additives at full strength in Grobo, at least not at first introduction. Currently you are adding 5mL (teaspoon) to whatever amount your Gobo takes in (a little over 2 gallons based on your observation), so would kinda have to guess as to the ratio of your mixture. Champs, what are your recommendations on running Big Bud?