hi again i have put my light's onto 12/12 a week ago and started using bio canna flowering but some of the lower leaves have started to go yellow. i have checked the ph side of things and it's all ok. i even did two run off test's and that side of things is fine so i'm thinking the bio canna flowering is lacking in Nitrogen the npk on the bottle is 2.5-2.0-5.0. i'm thinking of swapping over to mg all pupose is this ok for flowering? and what could it do to the plant swapping nute's? thanks allan