I have 5x 16l fabric pots and I used 50l canna coco professional plus + 25l of perlite. I didn't let the seeds to germinate, I put them straightly into pots on 28th June. 2 out of 4 RQS seems to be alright but this one looks the worst. I was using water (spray) without any nutrients untill 6th July. I put there 3ml Canna A+B, 8ml Canna Rhizotonic, little bit of CalMag and about 10l water. (10-20% leftover). Then I was watering about every 2 days - (10-20% of water went away) till today. Thank you so much

What is the substate NPK ? How often did you water ? She seems like she has had too much of nutrients. As plants are young ,they have their nutrients stored in the seeds so they don't need some other and will actually be weaker if they get some. Let her grow back all is not lost yet. Good luck !