slight browning, thoughts?

im on week 3 of veg, problem only occurs on lower, older foliage...i first saw the problem on the original fan leaves, cut them off and wrote it off as something that just happens(as many people have said) but now the problem has spread to the first true node, plant has 5 nodes now

see for yourself


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Are you feeding them anything? If you are, you might be giving too much...Which will cause the newer growth to be neon green almost, and your oldest leaves will get little burnt looking spots on the tips of leaves, I also see that your leaves are looking a little crinkled, which is also a sign of too much NItrogen....so...something to think about is just giving them water for a couple cycles and then go back with the nutes, or you could decrease the amount you are feeding each time.

dwc system 11 liters of water per 5 gal bucket, 4ml per liter grow, 2.5ml per liter micro, 1ml per liter bloom, using junglejuice grow micro bloom

Well whatever you are giving them they look like they feel it is too much...so ease off a little bit..just lower the concentration a tiny bit...definitely with N...