Is she a lost cause already?

[Rev11]

nevermind.

 

[agito]

you need to add a tiny bit of nutrient to rockwool as it contains nothing

its not a novice medium

 

[Rev11]

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[agito]

in a low nute seedling mix note low not 0 nute only other thing it could be is a lighting issue
and when you ph it you need to ph a couple points below your target as rock wool buffers back up

 

[Rev11]

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[agito]

I'll let the led lads chime in but i think your to close to led for seedlings and lack of nutrient has not helped
would be my guess.
rockwool should only require 1/2 a squezze to have enough air

 

[Northern Grower]

You said you ph'd the water. What ph was it? Tap water or RO?

Yellowing that early is usually a PH thing. The cotlydons should support it for at least a week. Even hungry seedlings. Did the shell membrane stick to the cotlydons when it shed the seed shell? Some times if it doesn't shed the seed right it'll score the cotlydons and they will show damage from it.

How is the new growth looking? Green or pale?

 

[Rev11]

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[Northern Grower]

Assuming you haven't ph'd the distilled water. It should have a ph around 7 from the bottle. I've had some that was near 8. As it's not PURE deionized water the ph won't be exactly 7.

If you look at the chart you should be a near 5.8.

Growing in water requires PH tools, EC meter/TDS ect. You really need to know the PH, and be on top of it. Not as forgiving as soil.

Once you have the PH where it should be then you can worry about feed. If the PH is off, the food won't be available to the plant for uptake. Which is when you see yellowing, necrosis. ect.

 

[Rev11]

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