I am sprouting a variety of strains in soil and I seem to be having an issue with a few plants. They are curling downward. I can assure they are not being over watered, but have only just begun giving light doses of nuts. They are growing under t5s with temps in the room at 18/25 Celsius. RH around 40. pH 5.5-6
Has anyone ever experienced this?
What kind of soil you in? That humidity seems awful low as well. I bet @elheffe702 could shine some lite.
Are they still in solos? If so they could be root bound.
I agree with @BobbyDigital, looks like unhappy roots. In soil the pH should be nearer 6.5, but anywhere 6.3 - 6.8 is fine. Could also be root bound in the cup. Transplant them into bigger containers when you can. Looking green and happy, otherwise. 
Yeah I was thinking the same, but I’ve taken my seedling much longer than this in solo cups without any issue.
I’m thinking I let the pH of my soil drop a bit. I’ll try and correct it next watering.
As far as the humidity, its prob the best its gonna get without a humidifier… i’m misting them several times daily to try and help.
