New Grower pH Problem?

[jayrocked]

Problem: Plants are showing signs of yellowing on its top leaves. I either suspect ph or too much light. I double-check my pH every time I water and try to keep it around 6.5. When I started noticing these problems I ordered a cheap but well-rated soil tester and its reading around 7 (Picture posted) but I'm not sure how accurate this is. Early today I watered for runoff and the ph was around 6.

Medium/grow method: 60/30/10 mix OC,HF, COCO and Perlite

Feed: and supplements used: Emerald Harvest: Calmag, Grow, micro, bloom, with some recharge and fish shit- Last time I watered the PPM's were around 650

water source: Springwater ph'd to and around 6.5

Strain/age: Mephisto Genetics Samsquanch- 46 days germination

light used: x2 mars hydro sp250's

Climate: Humidity 55rh temp: 78 degrees F

Additional info: The plant started showing signs of this problem about a week ago.

WORST PLANT (Samsquanch)

This is my 3 Bears OG

Emerald Harvest Feeding Chart

If this is a pH issue I'll seriously consider growing in coco. It seems like these amended soils can be unpredictable

 

[Diamond Dog Hair]

 

[Diamond Dog Hair]

Hope this helps ya. I've just started my first grow, but I RDWC.

 

[jayrocked]

Okay.. From what I'm seeing though.. If the plant isn't getting say, enough manganese or iron. What would cause that? Not nuteing enough or lockout? Ph problem? Because I am giving them nutrients so those things should be in there. It seems like either it's not enough or something is keeping them from receiving what they need.. Hence a ph problem.

 

[GeorgeCloney]

That was a lot of text dude...keep it short and simple in the future, just my advice.
6.5 ph in...what is ph out in the runoff?
Did you calibrate your ph pen lately?

 

[jayrocked]

Sorry... I just wanted to give enough info. I calibrate my pen every time I use it. Runoff was around 6

 

[GeorgeCloney]

Okay.. From what I'm seeing though.. If the plant isn't getting say, enough manganese or iron. What would cause that? Not nuteing enough or lockout? Ph problem? Because I am giving them nutrients so those things should be in there. It seems like either it's not enough or something is keeping them from receiving what they need.. Hence a ph problem.

Ok...Lets step back a few steps so you understand the full picture.

This explanation will be really simplistic just to be understood( no insults intended).
Ph is a scale that goes from 5 to 15.
7 being in the middle...most city water is adjusted to about 7.
Cannabis grow best around 5.5 to 6.5. on this scale.
Some better around 5.7 some around 6.5
Coco as a medium is 5.8ish....Foxfarm Promix HP..( peat etc...grows best around 6.1 to 6.5).

 

[GeorgeCloney]

Sorry... I just wanted to give enough info. I calibrate my pen every time I use it. Runoff was around 6

I don't want to sound like a jerk but...wishing to give you good advice...ok(?)
You should not have to, check/ verify your ph pen every time you use it.
If you do, buy a better pen...it will cost you less.

 

[jayrocked]

Thanks for the response. I know what my ph should be for soil. I don't check my pen every time because it sucks. I do it for peace of mind. I just want to advise on my leaf problem and possible causes. The soil ph tester reads 7 and my runoff was around 6. What would cause that? and how to fix it.. If it is indeed a ph problem.

 

[Diamond Dog Hair]

I don't have much experience and i would hate to give you advice. Sulfur and Iron uptake are available through a wide Ph range so it could be Lack of or possibly locking up when you mix you nutrients? I don't have knowledge with soil. I decided to grow Hydroponically with Autoflowers because soil seemed like to much of a variable for an Autoflower time table.