Help! Is this K or Magnesium deficiency - Or?

[Wolfski86]

Hi guys.

First indoor grow in years. Everything was going great until bang....! Ill post some stats and pics below

Strain: Black Domina (Indica Dom)

Medium: Organic Rich Soil $$$

Light: 200w 6400k CFL (switched from 130 w CFL less than a week ago)

Heat: Between 25 - 27 C

Humidity: Between 50 - 70%

Ventilation: 4" Vivosun inline fan.

Watering: I think I over-watered them about 4 days ago. Im letting the soil really dry out this time around.

CO2: was using pads, switched to exhale bat but took it outside the tent as I got paranoid. Its sitting right beside open screen-vent.

Cycle: 24, switching to 20/4 this weds and 18/6 in a week once I get my LEC/CMH

Age: ~ 3 Weeks from Seed/~2nd Week Veg

Nutes given: None other than root stimulator, I've been doing some foliar feeding to try and help them but feel like Im grasping at straws - feel may have helped a little. I did use some nematodes to deal with fungus gnawts.

Water Ph and PPM going in: Ph of 7.1, ppm ~ 133

Coming out: Ph of 5.5 and ppm of 735 .

Ive posted another pic of THC bomb. Its starting to get it too.

Please help me guys.. . . . .

 

[Wolfski86]

Anyone?

Im thinking that its mainly a pH problem contributing this. Given the diff between pH of water going in and ph of water coming out is telling me the soil is very acidic to change it that much. I have an analog soil ph meter but Ive heard its shit (and before I measured run-off) it was telling me I had alkaline soil. Im getting a paper pH kit for soil for this weekend. Anyone have suggestions on easiest/safest way to increase soil ph if the testing does reveal very acidic soil?

 

[KushGod]

Anyone? .

Im thinking that its mainly a pH problem contributing this. Given the diff between pH of water going in and ph of water coming out is telling me the soil is very acidic to change it that much. I have an analog soil ph meter but Ive heard its shit (and before I measured run-off) it was telling me I had alkaline soil.... Im getting a paper pH kit for soil for this weekend. Anyone have suggestions on easiest/safest way to increase soil ph if the testing does reveal very acidic soil?

Dolomite lime will buffer the soil to neutral but not sure how quickly, baking soda will ph up as well but again not sure in doses

 

[PIGSLAVE]

Flush the plant with 1/4 nutrient solution to correct the deficieny (3times the size of the pot) make sure the runoff ph shows your back in range for soil (6.5-7.2) and DO THIS while transplanting to a bigger pot with better soil . this will fix her and she will like you in the near future as well! good luck and good grows keep us posted .

 

[PIGSLAVE]

also buy a real ph pen paper is NO GOOD

 

[Wolfski86]

Flush the plant with 1/4 nutrient solution to correct the deficieny (3times the size of the pot) make sure the runoff ph shows your back in range for soil (6.5-7.2) and DO THIS while transplanting to a bigger pot with better soil . this will fix her and she will like you in the near future as well! good luck and good grows keep us posted .

So which deficiency is it then?

I reckon its because ph lockout... The soil is super rich. After alternating between two foliar feeding solutions. Its doing MUCH better. One of the sprays has K and Ph and the other has N, Mg and Ca so not sure which spray is correcting the leaf symptoms.

I need to correct the lockout then the plant will be able to use the nutrients in the soil. The soil I bought is super rich organic soil with compost and other good stuff. Paid top $$$ for it.

I'm going with dolomite lime as above. My ph is scaringly low.

And I do have a digital ph pen. Ill just recal it. Im not sure how accurate it is after sticking it in run off water .