New Grower PH Soil Run Off / Lock Out / Why? / Best Fix? / So Upsetting dont laugh !!

[true]

Hi All,

Ive done some searching on here and Google but would like to clear up a few things.
I hope you can help

PH Run Off In Soil
1. What is the desired ph of the run off from soil?
2. Do I assume we want the run off similar to what we are putting in?
For me this is 6.2 to 6.6 using Advanced Nutrients PH Perfect Sensi range and base water of PH 8.3 (not adjusting up or down).

This morning I have tested the run off from my 15l airpots and plant magic soil. We are on 45 days of life and so far so good, my plants have grown really well topping out at over 1.6m tall (DP AutoUltimate).

Although I suspect things are about to hit the fan. Ive been loosing fan leaves at an alarming rate. Ive reported this about and most feedback is 'dont panic, we all loose the odd leaf'. I know its more than that, so Ive been checking the run off today. I suspect a nute lock out on Nitrogen and I think Im right. (only think)

I watered a couple of plants this morning with plain non PH adjusted water of PH 8.3.
It takes about 2 litres until a smidge of run off, so these ladies got 3.5l.
I tested this with my Blue Labs PH pen and got PH 6.2 out of one and PH 5.7 out of another.

Sums #1:
Water in PH 8.3
Water out PH 6.2
Difference 2.1
Take 2.1 and deduct this from 6.2 leaving me with PH 4.1

Sums #2:
Water in PH 8.3
Water out PH 5.7
Difference 2.6
Take 2.6 and deduct this from 5.7 leaving me with PH 3.1

3. Have I done these sums correctly?
4. If this is the case then how do I correct this imbalance?
5. Do I just up my water/feed PH by what ever I need so that my run off comes out at the desired figure?

Kind kind people of AFN I know this has been covered before but I have to say me and maths are a sad mix.
Im a real dunce when it comes to basic sums. I dearly want to get this right!

Also this has happened before on my last 2 soil grows.
6. Why would things grow so very very well up to now and then start messing up?
7. Is this an issue with my soil?
8. Do some soils handle PH better than others?
9. Why only the fan leaves? - Starts at the bottom and works its way up.
10. Why not affected growth rate? These girls are huge tall.

I would like to know whats gone on, so next time I can work round this.

The leaves just go yellow, wilt, go soft but not crispy, they feel limp and floppy.
Nothing much has changed in the room, no mad temps.. Everything is steady away but for these fast dying fan leaves.

Ive taken 15 pics, check out my album

This is how they look now, I know they look good but the camera does not show the hidden leaves dying

 

[The Elvis]

Wow those are nice. You do have a N issue going on there and that ph seems awful low coming out of your soil. What i would do is flush the soil and add Epson salt to the soil mix in water also id spray the leaves to feed from the top with epsom salt. Are you or have you been flushing your soil around day 30 or 35 ?

 

[The Elvis]

Are you adding garden lime? If not id put some right in the top of the soil water it in . It keeps your ph more stable.

 

[medic grower]

Same prop over here but i have a lock out + N overdose. Flushed 2 times now with Cana Flush but its not getting better atm. First time since ages that i run on soil and bäm ph issues arghh

 

[faded187]

them calculations aren't that great (imo) you calculated right, I just don't trust that way of checking, cause if ur soil was that low ur plants would not be alive. can I suggest spending $50 on an accurate 8 soil probe. best $50 I ever spent( no bullshit) my 2 cents: N def for sure, prolly mag too. cause that would make ur leaves limp feeling. lack of or lockout I don't know but if you had an accurate 8 you wold knw

 

[blue]

The chart is fine. I've given it out countless times and the only times i've seen it not working is when pens aren't calibrated properly or when too much run off is taken. Just the first 100ml or so will do.

I'll try and run through your questions.

1) 6.1 to about 6.4
2) Ideally yeah, if you water at 6.2, and your run off is 6.2 then your soil medium is almost certainly 6.2.
3) I didn't check the all, but the first one - yes.
4) Check your meters - recalibrate. Sounds really low for soil - did you add any additional ammendments? if this is all done, then keep trying to get it in range with feedings or you may need to do a proper flush (3 times the amount of water than the pot could hold)
5) It's a balancing act. If you need to raise your "medium ph" (soil) then you'll need to raise your feeding ph.
6) I've got a suspicion but i'll leave that to the end.
7) I personally dont think so
8) I always use good quality medium with buffers. Negate your chances of mishaps by getting the good stuff.
9) becuase as your plant cant get what it needs from the soil, it eats itself. The green going to yellow is the plant eating itself (lol)
10) Here's what i think.

Your plants look a little overwatered (they don't look N deficient in any way shape or form) infact they look dark green and droopy (which is overwatering)

I just think you're overwatering.

I can only think that you're pens are giiving false readings. If your PH really was that low, the plant would look horrible and dying and scraggy.

These are my opinions and appologies if they don't align with other views. But I think this could help.
Try lifting the pots to make sure their feather light before watering (before they droop from underfeeding lol)

Hope this helps

Blue ^_^

 

[Muddy]

With such big plants in such small pots getting an accurate run off reading is going to be hard and frankly, I wouldn't trust it. If those leaves are coming from the bottom of the plant and from the center, near the main stem, that's pretty common once they become well shaded from the rest of the plant. That yours are limp and floppy makes me think that could be the case. I'm not seeing any signs of an N deficiency. If the soil pH is low and causing lockout, it should show as P and K deficiencies with possibly some cal/mag as well.

What is the PPM of your base water? pH Perfect was designed to be used with RO water and to work properly, needs the PPM of the base water to be between about 100 - 150 PPM. I've tried using it with my tap water, which has a base PPM of 250. I had similar problems with the loss of the lower fan leaves showing exactly what yours are.

I would also suggest you invest in an Accurate 8 soil probe. Well worth it to know exactly where you soil pH is at. Much more reliable than checking run off.

 

[GoAuto6]

Rough Calculation Guide:

Here's some good info on ph.....
If your runoff pH is higher than your starting pH, use this equation to determine your soil pH:*
Soil pH = Runoff pH + Difference

If your runoff pH is lower than your starting pH, us this equation:
Soil pH = Runoff pH - Difference.

For example, say your the starting pH of your solution before it goes in is 6.5 and the pH of your runoff is 7.0. The difference is +0.5, so using the above equation:
Soil pH = 7.0 + 0.5*
Soil pH = 7.5

If your starting pH is 6.5 and your runoff is 6.0, your difference is -0.5 and using the above equation:
Soil pH = 6.0 - 0.5
Soil pH = 5.5

 

[blue]

Hey GoAuto are those maths right?

I got the formula from you about 4 years ago lol

If your starting pH is 6.5 and your runoff is 6.0, your difference is -0.5 and using the above equation:
Soil pH = 6.0 - 0.5
Soil pH = 5.5

Sums #1:
Water in PH 8.3
Water out PH 6.2
Difference 2.1
Take 2.1 and deduct this from 8.3= 6.2

Should that be 6.2 "Minus" 2.1 ?

^_^

 

[GoAuto6]

Good catch Blue!!!! I think tho like Muddy posted, this is no help do to the nutrient line up. Only because I just went through a bout with some soil that was a 4.2 ph and those girls looked horrible yellow brown spots crispy stunted just looked like hell. I don't see any of that going on here.....