When to transplant seedling

I have a WW seedling that is two weeks old tommarrow, but doesn't have any visable roots growing from my 1in rockwool cube. From what i've read I shouldn't transplant it untill it has produced lots of white roots. I germinated from seed (only one to survive from a group of five) in a prop tray with heating pad. I water two to three times per day depending on the cubes moisture. Currently the sprout is cm's away from a cool blue flor. blub. The seedling has started to develop its secound set of leaves on its second set of nodes. I'm going to transplant it to an ebb n flow system with a 400 watt hps light once it is ready. My question is shouldn't my seeding be showing roots by now (nothing not even the main root)? Can i transplant it in the next few days regardless of roots? Is this plant a dud?

I have no idea if its a dud....I think were there is life there is hope....you could prob get away with transplanting before the roots are showing....most experienced growers like to wait until then.... but if you are going to grow in soil you might just pull it off...good luck with that

I'd give it another week. Wait for some roots.