Hi 3liter pots so less than 1 gallon, 10 cm so roughly 4 inches, from seed..how old are they?
Was the coco pretreated? I did not pretreat my coco and I had cal/mg issues.
Light green to me is under-feeding nitrogen..
Pics would be nice, I have been able to follow the online canna coco grow guide with amazing results.. go here and enter your data..I can help you if you need it
2.Tank size=how much water are you mixing the nutes with
3.Schedule for you should be normal feeding (you can play with this one)
4. I have a Hanna meter so I take the ppm from that meter and enter it into the "custom settings" making sure I select Hanna PPM from the box to the right of it. (or choose soft, normal, hard water)
5. Is how you want your outputs
I have noticed that when I mix it is usually 30-40 ppms higher than what Canna says so keep that in mind..
Now hand watering, in veg you can go days without watering, it will probably need to be increased during flowering. If you wait until the top of the coco pulls away from the pot/bucket that is the perfect time to water. You will be able to see space/air between the coco and the top of the pot. The coco will pull away from the pot, hope that makes sense. I water when I see this..
I usually water until I see the runoff comming out then I water for like 5 more seconds (not that scientific lol)
PICS PICS PICS