Seedlings shrivel and die in rockwool

Troubleshooting
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1

From a fellow grower: Seeds germinate then seedlings shrivel up in rockwool.
I have a hydroponic grow cabinet 36” X 24” X 72, X330 Kind LED, fan, air filters, seedling tray, heat mat and some others accessories. I ph the rockwool cubes to 5.5-5.8, let them drain then put the seeds that were in shot glasses until tail are showing. Heat mat set to 75, add the rockwool with the seeds, put the dome top vents cracked and wait for them to sprout l. I have left the light off sometimes and on at other time. The seeds have sprouted both ways but they end up drying up. I have waited until I felt the rock is dry before adding water but I get the same results.

Strain: Sour diesel/Northern lights

Type (fem/auto/reg): Auto

Climate (indoor/outdoor): Indoor

Medium (soil/hydro/details): Hydro

pH of runoff or solution in reservoir: haven’t gotten to that step

Nutrient mix strength (EC/TDS): same as above

Light type & schedule: 18/6

Temperatures day & night: 74/73

Humidity day & night: 50-75

Ventilation: yes

AC: yes

Humidifier: if needed

De-humidifier: no

Co2: no

2

Following. Im about to be doing the same with 6" rockwool blocks. Though i plan on using a root riot plug for the seed then into the block.

3

80 to 85F is better. Sprouts dont like phosphoric acid, save the pH-down for nutrient solution.

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4

I just germinated a seed for dwc a couple weeks ago.
Seed went overnight in light peroxide water and then into the little hydro plug/basket and then into the bucket, air on.
Bubbles keep the medium moist enough if the water level is just below basket, drop to 3.5gal when you see roots in a few days to a week.
75F, .8 vpd, 174 ppdf or 15 DLI.

Also I squeezed my plug out a few times last grow but just took it directly from its own light peroxide bucket (5.8), stuck seed in without draining, shot a few drops of orca around and chucked it in for this one. They say it’s like kids where the first one you do you pay a lot of attention to. I guess so.

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