Yellowing and weird shapes for new growth

My first guess would be an overage, not a deficiency. Plants usually only lack calcium during flower. Whether that is a seedling or a clone, it looks fairly 'new' in which case it doesn't need a lot of anything. Lights could be too close. PH could be wrong (6.2-6.8). I would raise the light and flush with a gallon of PH'd water of 6.4. Let it dry out for a few days then add a 'mild' seedling strength general all purpose or vegetative fertilizer. Shouldn't need anything else till it gets a few more leaves and root structure. Good luck.

Check pH.. soil = 6.5-6.8 give or take a bit.. coco 6-6.5. make sure anything you give, water or fertilizer, is pH'd to that range and try to be fairly consistent. If you add the same amounts of fertilizer and have city tap vs a well, it'll be very consistent.. have to measure out ph up/down a few times to be certain, then not worry unless you see a problem arise in future. don't buy "ph up" products... white distilled vinegar works well for an acid. Just C, H and O molecules so you arent adding anything too whacky. (acetic acid - believe it is a ketone with the double bonded o? or .. can't recall)