Answer: A couple of things come to mind about your seedlings. If they have too much water, the roots won't properly form and the leaves will yellow. Also, if they are older seedlings, with at least 4 true leaves, they should be fertilized
weekly with a dilute liquid fertilizer. Potting mixes tend to have only a small amount of fertilizer in them for a transplant to use. So try cutting back on watering and giving them a shot of fertilizer. I hope this helps.
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