First ever grow - auto Blueberry

17 of March - The last six days the grown in height and a lot or small buds are showing. But unfortunately the leaves are still yellowing. Some even got small brown spots. I have read and compared to some pics from Google and grow guides, but I find it hard to differentiate the symptoms, so I have stopped with the nutrientsb and will give it a week without. Then I'll see if it's stop the yellowing from spreading. I have also trimmed some or the dead leaves. Other then that I been thinking about cutting some hours of the light. But the grow shop which supplied the seeds told me that no matter what the auto seed will flower and that they would grow more if given more light. But I'm starting to think the light could be part of the problem..