Starting at 3 weeks from seed, in one gallon of water....I do 5 ml calmag, 5 ml of bio marine and 5 mil of grow. (shake each bottle for 60 secs). For autos 5 ml is plenty. For photos I read the leaf tips and step it up to eventually 10 ml of each. I look at the leaf tips tips to "read" the plant. If they are white-ish after fertilizing I back off. I wait for the soil to get fairly dry also before watering (but not too dry) so that oxygen gets into the roots. This is the problem you have right now. that little tap root isn't seeing any oxygen, so it should be in a solo cup. Pierce holes around the bottom of the solo cup for drainage. Transplant at day 7 from sprout into a 3 or 5 gallon grow bag.
I let the plant dry out a little so the leaves actually droop a little because I find that the plant can be super responsive then. Picking up the grow bag will tell you if you need to water. If it feels light you'll know it's time. I feed a little each day to day and a 1/2 rather than drenching them twice a week. I have 5 plants in my current grow and I split one gallon between all of them every 24-36 hrs or so. They are 2 weeks into flower now so that might increase slightly.
When they are stretching I stay with grow formula so the leaves don't turn yellow. I measure them every day. When they stop stretching I start with bloom formula and equal parts calmag and bio marine. I base this off what the plant is telling me. Once you learn how to read your plants you'll be off to the races. For beginners I highly recommend Dinafem White Widow as it is very forgiving and is a great smoke. I stop the nutes entirely 2 week from finish. With autos I harvest when the trichs are milky and swollen. Amber trichs are degraded THC (CBN) and I find it makes me sluggish.
I use Gobox and I have good success with it. Some will disagree with me on some of this..and that's fine. This is what works for me..
