Something wrong help

[Platinum Princd]

Hey I’m growing a WW auto in a airpot using GH trio Nutes using a custom autoflower chart for said medium. Lighting is Hlg550.

I’m in week 8. leaves are starting to yellow on the top of the plant??? but here I’ll let you guys determine from pics. Could this be a cal mag deficiency I’m using cal mag obviously.

I dropped my ph meter (blue lab)
And watered a couple times before feeling like something was off while ph’ing water could this be result of ph fluctuations?
Any input would be appreciated help!!

 

[jodyhighrollr]

Could be from your pH being off. Looks like your plant is beginning to show signs of nutrient burn with the tips turning yellow and the discoloration. I have never grown autos but from what I understand they are more sensitive to nutrients. It also looks like you're a couple weeks out and your plant could be pulling something it needs from your leafs which is normal. What were you ph'ing at? Also I want to add I know some stuff but I'm not an expert so hopefully some other people can help confirm what's going on.

 

[PE636]

How far from the top of the plant to your light? Kinda looks like light stress to me.

 

[Platinum Princd]

About 3 feet ...

 

[jodyhighrollr]

Google pictures of what we said and compare your pictures to them. May be more helpful

 

[HigherTheHigh]

Looks like a calcium deficiency.