Droop can be a lot of things.

Normally too much water, but I don't know if this is possible with hydro. Is the nute level higher in one container? And why are they the same? You want different nutes for flower than veg. Oh wait, I guess you're not flowering since the plants are so small. The light threw me, it's normally used for flowering. That alone though shouldn't make the plants droop, I don't think so anyway.

Also too much heat. Temps should be below 90, but I've heard of good results with temps as high as 104. Sounds like that's not the problem. If it's too much heat from the light, the outermost leaves will start to turn brown and eventually the whole leaf will die. You want your light as close as possible with out putting the plants above 90, except when they are first starting out. As far away as you have it, I expect you could move it closer within the first few days. If you want to rule out the light as the problem you could try switching them and see if there is a difference.

I suppose the plants might not like vegging nutes with flowering lights, but I haven't experimented with this or heard about it. I know that often when the leaf edges and tips start to yellow (as I see in your picture) it is often a nute problem. Too much or little magnesium I think.

Good luck.