Help! Leaves are turning orange.

I am in week 6 of flowering, I have just started flushing my ladies yesterday. However I am noticing stunted growth with my buds, leaves turning orange not yellow, and buds going amber. Is this a PK deficiency, light burn? Any help would be appreciated.

Based on all the white hairs in the pic, I think your buds still have a few weeks to go before harvest. When you flush, you are starving the plants, so they freak out and try to salvage what they can from their fan leaves. The leaves turn colors and shrivel up.

Good luck! Peace

Flush toilets not weed

^^^^agreed. I do not flush plants. I lower strength of nute mix during the last 2 weeks because the plants don't need as much, but I never attempt to flush.

How hot is your tent?

70-78 degrees with 50% humidity.

Here's my 5cents.
If you look at that particular bud, its actually very leafy and burnt.
That bud is trying to reveg because you're using a HPS and its TOO close to that particular bud causing it to get too hot aswell.
Altough your temp is 70-78 at that particular bud it's not. This is why your other buds seem fine.

EDIT : also seems quite heavy on the N

Yeah it's definitely revegging, look at the rounded leaves near the top. Somehow your plants aren't getting 12 hrs of uninterrupted darkness. Check for light leaks and issues with your timer.

Also as stated the plants look overfed from the indications of the burnt tips. No reason to suspect light burn unless the light is too close for some reason.