Rooted clones hit the deck???

I posted this in my grow log but figure it'll get a bit more visibility here.

I planted three clones yesterday in my hydro system. All had well developed roots, although one was almost twice as big as the other two since it rooted about a week earlier. For some reason the two small one's hit the deck hard this morning - they looked quite dead, actually.

Key Details:
System - Hydro DWC w/ drip feeds
Aeration - two 5" disk style air stones w/ industrial air pump (in other words, lots)
Lighting - 400w HPS 4' above the plants; 18/6 cycle
Nutrients - Lucas Formula, 580ppm @0.7 (about 1/3 strength for clones); tap water (180ppm) used as a base. The whole mix was allowed to sit for 36 hours before planting to stabilize (yeah, right)
Res Temps - 82F
Ambient Temps - ~80

Pics:

http://i267.photobucket.com/albums/i...o/_MG_1640.jpg

http://i267.photobucket.com/albums/i...o/_MG_1641.jpg


Any ideas, anyone?