Green leaves with copper colored spots on the edges

Hi guys,

Attached is a picture of one of my plants. Just started going into first week of flowering. Light has been adjusted to 12/12, and nutrients have been adjusted for the flowering stage. I'm using Foxfarm Ocean Forest potting soil, Earth Juice nutes, have a pH tester, and use an eyedropper to measure the ingredients,

On two of the larger plants, I am starting to see spotting on the outer leaves, with coloration going from copper to a light brown. Any thoughts on what may be the cause?

Thanks,
Bob

looks like a cal/mag deficiency to me. where is your water coming from

Looks like calcium to me as well... if you are using reverse osmosis water you have to add cal\mag.