User blog comment:Rozzaruner/Hello Black Flash/@comment-27339258-20160525154509/@comment-27700324-20160525164658

The only reason Eobard's lightning was red was because he artificially gave himself speed with the tachyon device. I have no idea why this doesn't affect the Velocity 9 users, but that's just a plot hole of the show.

Maybe because of his use of Velocity 9 and being in the speed-force purging center, he will come out with red lightning.