First Grow - need opinions!

[Pal23]

Hey guys, so I have posted these pics to my grow journal so I'm sure I'll have answers soon - this just seemed like the best option for getting a few opinions on my plants health. I noticed some brown/rusty looking spots appearing on the leaves around the main cola - is this a deficiency of something other than magnesium? (Both plants suffered from unstable ph and mg def prior to this) if it's just the continuation of mg def I can remedy this, if not, I need to know what to do next to save her Thanks for any advice in advance

 

[SmokeyDeHerb]

If you've had pH problems it could be that. Check your water pH going in and runoff. As a general rule the difference between in and runoff is about half the pH of your grow medium.
For instance if your water is 8.0 going in and the runoff is 7.5 your grow medium pH will be roughly 7.0.
If your grow medium pH is too low (around 6.0) you could have lockout. I had a similar problem on my last grow, pH too acidic and rust spots on the leaves. Hope this helps.

 

[kushaddict]

If you've had pH problems it could be that. Check your water pH going in and runoff. As a general rule the difference between in and runoff is about half the pH of your grow medium.
For instance if your water is 8.0 going in and the runoff is 7.5 your grow medium pH will be roughly 7.0.
If your grow medium pH is too low (around 6.0) you could have lockout. I had a similar problem on my last grow, pH too acidic and rust spots on the leaves. Hope this helps.

I may be high, but I just sat and looked at this comment for ten minutes trying to figure it out. Today my watering was a ph of 6.7 in and 5.7 runoff. What would that be?

 

[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​

 

[kushaddict]

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​

Wow that made it much easier on my brain. Im saving this for future use lol.