Problems after flushing soil can anyone help?

[kronos416]

Well i have a few moms that looked like they were suffering from nute burn do to the tips of leaves yellowing. so i decided to flush. I ran double the amount of water for each plant and container with Ph adjusted water at around 6.5. been using organic soil and i use fox farm grow, and diamond nectar. plants started showing necrotic spots all over leaves ( lil brown dead spots on leaves) tips are dieing and curling upward. some plants are also showing where leaves are fading except for vein areas which are staying darker gree color. the leaf tips are a crispy crumbly. Im haveing a little probs diferenciating between what the plants are lacking because a few of nute deficiancies are similar. could they be lacking Ca calcium because of lil bron necrotic spots on leaves? K potasium which also shows necrotic brown looking spots on leaves + some of leaves are turning yellow and dieing off, just a cpl leaves really not even enough to mention but thought i would anyways.... Mn manganese which also shows necrotic spots on top of leaf? or Mg magnesium where some of lower leaves are turning yellow then drieing or dieing and where some leaves show yellow but veins remain green and tips dieing curling upward? How can i really tell what is what when so many similarities in diagnosing the problem? any help greatly appreciated

[motorheed]

got a pic mate?