Roots Organic Amendments...I Have Some Questions.

OK! so im on my 3rd crop im about to harvest and im having the same fucking problems as i had with my second grow. 1st grow had some issues but i think i solved them. i have some aphids. and im only growing 1 plant because of it. i was on a perpetual garden system and the bugs slowed everything down. my plant is the end of the 4th week of flower. last week the leaves started going necrotic and yellowing. this has happened a lot with me and i have been told it could be several things. Nitrogen, the bugs. could be a manganese def. i do not know what to do. i upped the nutes 5ml. and do not see any change yet. im a little nervous. my yield is decent. i yield about 1-2 ounces per plant, on average. i have also been told that i need to chop off the bottom 1/3 of my plants and support the top branches with support stakes. which i have done this grow and the last. but the buds are only a little bit bigger. im getting off the main def issue here. but i need to know why the leafs are going necrotic and an un-even yellowing. i know nitrogen is a even yellowing. the yellowing is not even at all. and is kinda all over the place. i have not given it much concern because i have aphids. my medium is Sunshine Mix Advanced #4. i have been keeping my ph at 6.5. what am i doing wrong here??? if you need anymore info, i will provide it. and sorry for the lengthy question.

Where is your water coming from?

i use reverse osmosis. and i use the Cal/Mag every so often. one thing i think i have done is may have over done the Cal/Mag. i used it with every watering up til about 2-3 waterings ago. could this be a salt build up? should i do a flush maybe?? i am also using Botanicare nutes line. Pro Grow, Liquid Karma, Hydroplex, Sweet-Raw and Hygrozyme for the root system. but i heard becaus eim not in a fully organic medium (which i really want to switch to the Roots) that it does not work as good if i was in a complete organic medium.

Well I can only say from personal experience. Recently i think I over did cal mag in a feeding after not giving it to my plants for weeks. I think I did start getting some small issues but flushed and then hit it with my organic tea and my plants seem to have bounced back quickly. This is the first issue Ive run into with cal mag since I have started using it. My next question to you would of been if you were using cal mag but you are so Im going to keep my eyes on this thread and hopefully you can get an answer. Good Luck

thank you very much. im just hoping that once i switch my medium to Roots Organic, i stop having these issues. i also have about 60 strains in seed form, im having a very hard decision to make on what to grow next, and what will be thee tastiest and easiest, lol. but ill save that for another thread.