T5 L.E.D. 4' - 4 lamp fixture hanging height??

[PLantAsEED]

Just picked up a 100w T5 LED Jungle fixture by Plantmax. Unsure on what height I should hang it. 6" above plants like fluorescent, or 12-18"+ like the QB LEDs that I use?
Some Background;
Sprouted a few seeds (Humbolt Dream) almost 10 days ago under T12 bulbs that sat in a grandparents basement for who knows how long. Unfortunately they are still on their first set of true leaves and about 6" tall and lanky....Unsure if they will recover. Went to local grow store for a ppm meter and there was sitting a 100w T5 led fixture right by the door for a good deal, so I bought it. Just hooked it up at 6" above the seedlings and I am unsure if that is appropriate?

 

[PLantAsEED]

Photo for visual description

 

[Grapefruitroop]

I was just lookin on the web to replace my t5 fluoros with half of wattage in LEDs! Sounds a very good deal!!! Im in Too!!
I was wondering your same question and based on my other 100w fixture (where diodes are much more concentrated, ina round) id be careful and prolly start farther for seeds or clones....but maybe the fact that the diodes are much more spread will mitigate the blast of light!

 

[Grapefruitroop]

After playn with em a bit i found perfect height about 50cm from canopy for clones and 30 for vegging....so forget about the shitty coverage of T5s this things are amazingly bright...
And of course...boost the Mg!