What to do with these roots?

Well I might have jumped the gun and germinated my seeds a little too quick, as my vegging equipment isn't here yet. All 10 seeds gave a tap root within 48hrs and I then transplanted them into Root Riot starter cubes. Now today (less than 48hrs after going into cubes) a few of them have a white root hanging out the bottom.

Now I just have my Root Riot cubes in little 2" net pots sitting in a 10"x20" cut tray. I'm freaked out because what do I do now that some already have roots hanging out the bottom? I put just enough water in the tray to fill some of the grooves in the bottom. I then put the net pots with roots showing over the grooves with water.

Is this ok to have the roots hanging out of the bottom for a few day? I didn't think things would move so fast. It might be a week till I get everything. I do have some hydroton. Should I put some in the tray and fill with some water, then put the net pots on top?

Can I just leave them in the tray and water them by hand for the next week?

Thanks

I would put them in the hydrotron then back into your trays.put just enough water in the tray for the hydrotron to wick it up.

the roots should be touching the water, don't let them hanging in the air