[PooToe]

@PooToe
You run FloraNova nutes right?

Didn't know if you had any advice for the OP with the nutes.

If you've fortified the soil prior then my guess is the feed strength is too high which is why you're getting the burnt tips.

OP what percentage dose are you giving the plants? 50%? 75%? Full dose?

Could also be signs of a high light energy. When you turn up your lights you also turn up the plant processes happening. Could be your plant pulled whatever ion it wanted at the time to keep up with the light energy it was using in photosynthesis and is now high in other ions it didn't use and it's locking out burning the tips from too high a concentration of other ions.

I'd try and back off on the feed first to see if that helps and check the light output to see if I'm in range. If the light energy is too high then you can back it off some and see how that does for the plants.