Potassium Deficiency?

Hello all,

I am hoping someone may please kindly lend their expertise and advise if this is a potassium deficiency and if not what it may be?

I'm using debco premium potting mix and Debco pot mate potting mix. Next time around I will be using coco coir. They're under a 600wHPS, there is a tower fan in their blowing on them whenever the light is on. There is also an inline fan cooling the hood.

Temperature: 22-25 degrees
Humidity: 40-50%
PH: 6-7 (usually 6.5 to 7) but I water with 6-6.5 ph water which is airated
Feeding with Advanced Nutrients Ph perfect BLOOM and MICRO
I have used THE ROCK nutrients as well

I flushed last night and plan to feed again today

Thanks for any and all help.

Stick your finger in the soil and feel the temp and wetness , looks like a lockout from over-watering and cold soil temps when lights are off.

How far is the light from the tops? How much feeding u giving them...

Trow some cal-mag and silica... (dont give em nutes for a whole week)

Spray them also with low dose silica... try to keep temps a bit cooler if possible... they really look sick... I hope thye cna get back up and running they hurting bad.

Report Back

-Jugz

Thanks, I will try and use some cal-mag and silica and go without feeding them for a week.

The light is about 12 inches above the canopy.

They get about half the nutrient suggested on the product.

Can I spray with the Silica even while they are flowering?

The soil temp probably does drop when the lights are off as it gets quite cold but there is nothing I can do for that...although it would be quite a feat for the soil temperature to drop drastically in 12 hours while the lights are off. I imagine though the ambient temperature around the plants could suffer a big temperature drop when its really cold here getting down to like 10-15 degrees when the lights are off.

I knew overwatering can cause issues in the plant I didn't realise it could cause a nutrient lockout.

thanks again for the suggestions