the gravity seemed to get beter results in the drip than in the soil plants i used it with but the p.maxx increased resin production in soil and hydro after about three days use but it didnt turn n e of my girls purple i had a buddy who ran it outdoor and his turned purple the last week although it may have been the strand considering it was bagseed we didnt really know if the purple was genetic or a result of the p.maxx