I don't see why you'd want to keep them in darkness at all. You want them to start vegging, putting them in24 hrs of darkness is kind of the opposite of them. But who knows, I haven't started cloneing yet.
I never put my clones in the dark...I dont know where you got that I run all 24/7 and so the clones go right into 24 ???on the dark....how do you keep em from droopin??