Light spectrums for vegging autos?

How long should I run blue while vegging my autos? Or should I run both? It gets a little warm when I run both(84f).
I'm running 2 pro grow 180's in a 4x2x6 tent. I have five 9 day old plants. They're about 2 inches tall & starting to get 3rd set of leaves.

i dunno if they are autos or just have some in them but i had a hell of a time keeping certain strains fro flowering under blurples

6500k T5s got em back to pure veg.