Tiny seedling at 3 weeks

Three weeks old? It's color is very important and can tell you a Lot about how healthy your plant is. Same with leaves. Leaves will give you clues about the health of your plant and any deficiencies it might have. Now, the color of your plant tells me it is growing it wet soil. Give it a few days without watering and then scoop out some dirt and give it a squeeze. If it stays packed together, don't water it and wait another day. Then, do the same test until the dirt won't compact when you squeeze it. When it falls apart after you squeeze it, it's time to water. I hope this helps. Good luck!

@paddy76 I have to disagree with the others on this it is needing nutrition but its not thru a lack of nutrients in the medium the problem is overwatering . the roots are suffering and unable to uptake what the plant needs Let your grow medium dry a little between waterings so that roots can breathe master the watering issues and you will get better growth from your plants

High Paddy, She doesn't need nutrition yet. Even when you grow in lightmix this girl did not even develop a serious root system yet to be able to process all those nutritions. There is still plent of virgin soil and nutrition left. The problem here is that the soil is too wet, you can see that she needs oxygen from her leaves bending down like a claw. Because the roots are suffocating her grow is stunted. A little girl like this doesn't even drink a full shot glass with water per day. Just let the soil dry out and only give water on the outside of the pot. They love to search for the water and this is what you want the roots to do. Happy Growing! 😋

it looks to be hungry, cotyledon will fall off normally and nothing to worry about. I would look into what is in that soil and if it is depleted or needs something extra. Keep an eye on how much your watering as well, an over watered seedling can die quite easily or be stunted heavily. Good Luck!

The cotyledon leaves are nothing to worry about... I think this little girl is very hungry! I would start her on some grow nutes - about 1/2 strength to begin with - and you should see an amazing turn around! Good luck!