Hard to answer without more information on what you are feeding. You are obviously feeding them sufficiently since the leaves and buds look healthy. It probably has strong enough PK too. So, are you asking whether you can just add BB to what you are currently giving, without decreasing the dosages? If so, I would say probably not.
[/QUOTi have them growing in 1 part promix 1 part happy frog 1part ocean forest, after 4 weeks gave .5ml micro, grow,bloom, between feeding, blackstrap molasses. About to give 2nd feeding of micro, grow bloom gonna up it to 1ml of each..can I add the big bug too now? This will be roughly 41 days in.