Potassium Deficiency - or ?

by2 said:

temp 70-80f, 50-60% humidity. I only have one AC infinity fan above the canopy on low speed.

Click to expand...

Oops, thoughts #16 was you.

At 70° and 60%, that's on the cooler side so RH of 60% will get you into seedling VPD-wise. That's slow nutrient uptake.

80 and 50 is a tad "high and dry". Going from a VPD of 1.2 to 1.5 is a 25% increase in transpiration/water uptake/nutrient uptake.

OneHitDone said:

Is that correct that you have no Sulphur?
Some of the micro's look very low also.
I've been running a scratch mix that looks like this.

View attachment 5464524

And getting growth that looks like this in aero/hydro

Click to expand...

Great taste in computers.

Delps8 said:

Oops, thoughts #16 was you.

At 70° and 60%, that's on the cooler side so RH of 60% will get you into seedling VPD-wise. That's slow nutrient uptake.

80 and 50 is a tad "high and dry". Going from a VPD of 1.2 to 1.5 is a 25% increase in transpiration/water uptake/nutrient uptake.

Click to expand...

I know but can't do so much about it. Don't have any measures to deal with temp and can only dehumidify the lung room so that wont help.
And I don't think it's so bad. The temps right now 78f and 48%. Last night 68f and 55%.

by2 said:

I know but can't do so much about it. Don't have any measures to deal with temp and can only dehumidify the lung room so that wont help.
And I don't think it's so bad. The temps right now 78f and 48%. Last night 68f and 55%.

Click to expand...

Those are a bit cool, overall, but nothing that would cause any issues.

With the information that you've provided, everything should be doing great. Given that it's not, what parts of the grow environment (attached) could be out of whack?

Another thought - this "isn't your first rodeo" so what's different for these grows from your previous grows? Anything in water source perhaps not being stripped out by the RO unit? A change in the equipment, perhaps? Grasping at straws here.