hey there bro well i dont know bout drip/bubbler hydro systems.. but when you switch to flower 12/12 you simply swich the lights from what your on now 18/6 to 12/12.. as for bud nutrients most growers use veg ferts for the first week of flowering as its high in nitrogen and lots of plants lack it early in flowering then go straight on to flowering ferts but only like a quarter the recomended dose.. opps i just realised that no posting questions to.. o well ive wrote this out now im sure it wont hurt.. and if it does hey im so sorry