Yellowing tips

Agree with overwater, lights can do this. Gnats also.

Hey, there's quite a bit of information missing, but something similar happened to me a while back. Here are some things that could cause that symptom: Light and heat: Your light is too close to the plant and has burned it. Sometimes it's due to excessive heat, and other times just because of the light intensity. This means there might not be a high temperature, but your plant could still get burned because of that. Ideal conditions at this stage are 22-26 degrees Celsius and 60% humidity, so try to maintain those values and move the light away if it's too close, depending on your light's intensity. Water spray: Are you misting the leaves constantly? This causes water droplets to form on them, and the light acts like a magnifying glass, leading to leaf discoloration. Avoid spraying directly on the leaves, or at least try not to leave water droplets on them; gently dry them with a soft cloth. Nutrients: Excess nutrients can cause this too. If you haven't applied any extra nutrients yet, skip this point. Even if the substrate is prepared, it's unlikely to cause these types of symptoms in the plant; they usually don't have THAT many nutrients. Ventilation: Do you have a fan pointing directly at it, or is it too strong? Try not to point any fan directly at the seedling at this stage; the fan should circulate air more than anything else. It shouldn't be on the plant for too long, as it can burn it. Beyond that, the seedling looks healthy. Just keep checking these points calmly. Control the watering and misting properly! You'll find out how to do it well by just googling a bit if you haven't done so already. Good luck!

A picture in white light would be easier to see. Do not give any nutrients. Your plant is barely above ground and still very fragile. If the tips of the leaves are turning brown and you haven't given nutrients your soil might be too hot (too many nutrients).

Need more info. Soil? Peat? Coco? Are you feeding her? If its promix or coco and you're feeding her stop. Just water for a week.