What deficiency or problem is this ?

Trying to figure out the issue with my plants.

The problem started out as light green/ yellowish fan leaves at the “top” of the plants. Its quickly progressed to brown spots on the fan leaves – Fan leaves on lower part of plant look pretty much green and healthy.

Also the Top portion of stems are turning completely purple. And the Leaf petioles are purple as well.

The plants are in Happy Frog Soil with a little extra Worm Castings added.

They are being fed with Earth Juice Seablast Bloom nutes and 3ml per gallon of Botanicare cal-mag. – I PH adjust the nutes to 6.5 then hand water.

I fed at 700-800 PPM’s first couple of weeks. Just bumped it to 900 PPM’s last couple of waterings.

The plants are under Gavita Full Spectrum LED lighting and in week 4 of flower.

Can’t figure out what’s going, any opinions would be greatly appreciated.

Looks like a Manganese deficiency. Odd since the Earth Juice Seablast Bloom is said to contain 0.10% Mn., at least according to a sellers comment.

twentyeight.threefive said:

Looks like a Manganese deficiency. Odd since the Earth Juice Seablast Bloom is said to contain 0.10% Mn., at least according to a sellers comment.

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Maybe under feeding then ??? - Thanks for posting the link !

Are we overwatering? Overfeeding leading to lockout?

JoeBlow5823 said:

Are we overwatering? Overfeeding leading to lockout?

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Possibly Overwatering - Letting them dry out a few days right now. Dont think overfeeding, maybe underfeeding if anything. I tend to be on the lower end of ppm's

Dono123 said:

Possibly - Letting them dry out a few days right now. Dont think overfeeding, maybe underfeeding if anything. I tend to be on the lower end of ppm's

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FWIW anything over 900 ppm on my last plants and they started showing burnt tips. Fed at 1.8 EC or 900 ppm with great results.

twentyeight.threefive said:

FWIW anything over 900 ppm on my last plants and they started showing burnt tips. Fed at 1.8 EC or 900 ppm with great results.

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Roger that - Just started the bump up in PPM's since they are in week 4 of flower. The problems started when I was at around 700 ppm
Also, Seablast is mostly organic nutes, more forgiving than salts.
BTW im using tap and before anything is added my tap is at 400ppm. The 400 is "included" in the PPM numbers above. So I may be on the light side as far as actual nutes go. Any thoughts on that ??