Brown spots on seedling leave?

These seedlings are exactly 14 days old since I started germinating them. Out of all of them, one is showing some brown spots on it. They are still in the rock wool cubes and will be going into a RDWC. They’ve been getting very small amounts of RO water with a little Armor Si and Rapid start from GH, and calmag. Ppm of that mixture was between 200-300 max. PH around 5.8-6.0. Temps are about 78-80 with humidity around 65-70. None of the other 4 seedlings are showing anything like this. Any help would be appreciated. Thanks!

Too much light, try keeping it in the shade

13lueCheese said:

Too much light, try keeping it in the shade

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I have 8 other seedlings that are literally right next to it and none of those are showing anything similar, so idk if it could be the light. Do you have any other ideas?