Coco has been twicely buffered with Cal-Mag and mixed with 30% perlite (growing in a 16L root pouch).
At day 4 I decided to top off the twin seedling as I want to obtain a good yield with one plant, leaving aside the fact that transplanting the seedlings would have been a dangerous operation.
I also watered the seedlings with 6.0 ph 0.5L water + Cal/Mag , I am expecting to see the first set of true leaves to increse size over the end of Week 1.