HELP! Yellow tips on new growth

[JohnnyJohn]

I have 3 autoflowers going and they just started to show signs of flowering a few days ago. Zero problems up to this point. One of them is starting to get yellow tips on all the new growth... Does this look like a deficiency or does this just happen sometimes? It's Orange Sherbert by FastBuds. Grown in FFOF with the bottom 1/3 of the pot being Nature's Living soil mixed with the Ocean Forest. I have added nothing but spring water and a layer of worm castings as a top dress. Thanks for all your help, new to the scene here! Here are two pics, it looks worse under the LED light (spider farmer sf2000)

 

[CaptainWiese91]

What is the Ph levels ?
How far away is the light ?

 

[Farmbuck]

I might be wrong, but it looks like light burn to me.

 

[CaptainWiese91]

Could easily be. But the pictures makes us hard to see the other lower leaves properly. If it’s only the top leaves which are doing this, then I would say light burn also

 

[JohnnyJohn]

Ph is around 7, but I don't check very often since it's all organic. I've been using the same bottled spring water. I did back off the light a bit. It was around 18" from the canopy at 90/100%. Now it's 24" at 80/85%. Just weird that the other 2 plants haven't showed any symptoms like this one

 

[CaptainWiese91]

The plants are not the same, and have different desires and needs. Even between the same strain.
And yea you should check your Ph every time you water. Organic soil also need to be adjusted. Only if you have 100% living soil, you don’t need to check the Ph
And Ph “around” 7 is a little bit high. You don’t own a digital Ph meter ?