Any ideas what this is

Hey this is my other plant everything was going smoothly until 3 days ago. I noticed on some older leaves some yellow fading working it's way through the margins from the tips inward it's really hard to get to show on camera but I tried my best.its happening on upper, lower and middle of plant also the tips of infected leaves are starting to dry and curl backwards, I think it's a magnesium deficiency but want a second opinion.the strain is critical silver haze and she 5 weeks into 12/12 today being fed biobizz grow at 2.5ml per 2 litre bio bloom at 6 ml per 2 litre and top max 2.5 ml per litre.under 600w hps light is a fair distance from the leaves showing this problem here are some pics If the no good I will try and do more but the fading is hard to catch

Add 1 tsp of Epsom salts to 1 gallon of water, feed it and see. A shot of Magnesium won't hurt your plants.

curious2garden said:

Add 1 tsp of Epsom salts to 1 gallon of water, feed it and see. A shot of Magnesium won't hurt your plants.

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I gave a shot of magne cal by plant magic uk 2 days ago no improvement yet

giz2k14 said:

I gave a shot of magne cal by plant magic uk 2 days ago no improvement yet

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Better pictures are in order here because I can't really see much of anything. I have a guess but that's not good. Magnesium is a gimme. Turn off that HPS and get a decent picture of the overall plant and of the affected leaves in normal light.

What are the PPM and your pH you are feeding?

Best I can get mate not ppm using organic nutrients ph in is 6.8 ph out 6.6

nitrogen def.

chuck estevez said:

nitrogen def.

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Does it need correcting or leave her ride ?

giz2k14 said:

Does it need correcting or leave her ride ?

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I think you are close enough to let it ride, subcool likes his to fade toward the end

chuck estevez said:

I think you are close enough to let it ride, subcool likes his to fade toward the end

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I gave her a high dosage of bio grow 2 days ago as it's organics I won't see instant results so I will leave her go I might up her bloom dosage though see if that help can n def appear all over then mate