I’m surprised your plants are yellowing using the Hydrocrop nutrients. I have used them for 3 years, growing tomatoes semi commercially, and always found them to be excellent. Your diary says your pH is 6.5 …That could be where your problem is (assuming your growing environment is okay). To avoid deficiencies using mineral nutrients in hydro / inert media, the feed pH needs to be kept between 5.5 and 6.4.
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