Mag deficiency? In need of help.

[Iblex]

Heya!

Yhis might be the wrong part of the forum to ask but im new and couldnt really find my way to a better topic.
I got a 7 week old Jock Horror, and she seems to be in a serious condition

My guess is Mag def. But im not certain. Was hoping for someone to tell for sure what´s wrong.

Only got this one picture for now. The whole plant pretty much look like this now and is very yellow/pale looking.

 

[Floridian]

Yes that's what it looks like to me I had that issue for awhile.Are you using tapwater?How are the PPM's if your tap contains a lot of calcium it will lock out the magnesium.Get a clear glass and fill it with your water whatever your using,after about a week dump it and see if there is a calcium deposit film,if so your plants can't utilize magnesium

 

[Iblex]

Yes that's what it looks like to me I had that issue for awhile.Are you using tapwater?How are the PPM's if your tap contains a lot of calcium it will lock out the magnesium.Get a clear glass and fill it with your water whatever your using,after about a week dump it and see if there is a calcium deposit film,if so your plants can't utilize magnesium

Yeah, using tapwater. 160 PPM.

The other ones looks fine tho, same treatment, same water, soil, nutrients etc. She is completely stunned now aswell. :/

 

[Chilly Willy]

I am not so sure. The leaves should also show marbling. Can you show us more of the plant so we can see. Here is a link that shows the marbling, be sure to click on this picture and enlarge it the most you can, do not just look at the yellow in the leaf, look at the green portions so that you can see this marbling. https://www.google.com/imgres?
https://www.google.com/imgres?imgurl=https://upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Frangula_alnus_with_magnesium_deficiency.jpg/1200px-Frangula_alnus_with_magnesium_deficiency.jpg&imgrefurl=https://en.wikipedia.org/wiki/Magnesium_deficiency_(plants)&h=900&w=1200&tbnid=l-ugoqp_Odql7M:&tbnh=160&tbnw=213&usg=__wHPRO1x5Chu_-3ulBkBAEYMd5TU=&vet=10ahUKEwiU4I2bjqLVAhXs34MKHf_5AREQ9QEILTAA..i&docid=UusX2PeceszJYM&client=safari&sa=X&ved=0ahUKEwiU4I2bjqLVAhXs34MKHf_5AREQ9QEILTAA

 

[mushroombrew]

Marbling? Wrong species.

What is your pH? First thing you need to check. Dirt or Hydro?

Lets get you pH sorted out first. 99% of nutrient deficiencies are from incorrect pH