Yellow streaks hmmmmm.....

Wassup all. Haven't posted in a while but I've been creeping around rollitup.
Anyhow, I've got some new babies on the rise. They're 22 days old and under some HID's with a calculated 3060 lumens per sq. ft. But here is the weirdness.....
Yesterday the middle plant had these yellow streaks between the veins on one leaf. The rest of the plant and its neighbors look great. My lights were pretty close and I promply moved them.
It looks better today and the temp stays in the 70's. Watering is fine, soil ph is fine, I monitor the water ph.
I'm thinking the leaf got a little hot.
But has anyone seen a marking like this? Haven't changed any routine's yet, don't wanna freak out over nothing, but I need some expertise!!! HELP!?!?........please?

I'd say that would be from nute burn

Bonafide925 said:

I'd say that would be from nute burn

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It's possible but nute burn usually starts with yellow tips, and this is between the veins and only on 1 leaf so I wouldn't think so.
Have you looked under the leaf?

spiked1 said:

It's possible but nute burn usually starts with yellow tips, and this is between the veins and only on 1 leaf so I wouldn't think so.
Have you looked under the leaf?

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Yeah. It looks identical to the top. I didn't think it would be a nute problem because I haven't used any yet. Soil ph for that plant is 6.7 today. The markings haven't changed and the plant is still looking healthy, green, and first set of nodes are nice and green. New growth is larger than than the older leaves.