Nute burn or possibly Cal-Mag def?

Username85

Well-Known Member
So I’ve noticed a small number of light green leaf tips and wondering what could be the cause.
Someone mentioned to me nute burn, but looking up the symptoms it does look like cal-Mag deficiency.
I was feeding too often early on and wasn’t switching up with just water. The last 2 watering have been plain ph’d water-they haven’t seen nutes since April 23rd.
When I was feeding one feeding would be: 1.5 tsp FF grow big & 1/2 tsp Cal-Mag per gallon.
Next feeding would be: 1.5 tbsp FF big bloom & 1/2 tsp Cal-Mag per gallon
Each plant was given about half gallon at that point in time.
Hope this is enough info to help me figure this one so whatever issue it is doesn’t continue
 

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Username85

Well-Known Member
Might be important to mention. I have 2 plants side by side being fed the same and only the larger plant is showing this issue
 

Bose

Well-Known Member
Are you using full strength nutes? If so it very well may be start of nute burn. Fox farm is hot do you have a ppm meter if so what ppm are you feeding at.
 

Username85

Well-Known Member
Are you using full strength nutes? If so it very well may be start of nute burn. Fox farm is hot do you have a ppm meter if so what ppm are you feeding at.
I was giving around half or less than half the suggested amount. I think the Grow Big was suggest around 3-4 teaspoons and I went 1.5 and similarly for the Cal-Mag & Big Bloom. Last I remember the ppm going in was in the 600-660 range
 

Bose

Well-Known Member
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That or drop to 1 teaspoon on next feed. See how she responds. Sounds like you flushed her with the last two watering with only ph water.
 

xtsho

Well-Known Member
It's funny how quickly bro science shit like CalMag perpetuates the internet. I've seen you write less is more over and over and it makes so much more sense after getting it through my thick head.
I hear you.

So many people growing cannabis use tap water then worry about the chlorine or chloramine in their water but never even stop to think about the levels of calcium and magnesium in that same water. Which in most cases is more than enough for the plant. Most people don't even need to be using calmag but they do because as you say it's that broscience all over the internet. Posts like "I watered with X amount of calmag but it didn't help". Well of course it didn't help because the plants didn't need it. Now you've just messed things up even more.

Most figure it out after a couple grows but the bad information is still all over the place and that's what most new growers read or watch on youtube.

Plants need more P/K than Ca or Mg. Providing too much Ca and Mg can prevent the uptake of P/K. Ca and Mg are also antagonistic with each other. Nutrient Antagonism is a real thing. More is NOT always better.

I'm starting to wonder if so many of these problems people are having when not even using very high EC levels is due to the use of too much calmag throughout their grows. So many think it's a requirement but it might be doing more harm than good in many cases. People are using it every feed. It's going to build up in the substrate.

This chart is not the end all but just a simple starting point as to how different elements react with each other. If you're growing organic it gets more complicated. But with the typical chemical nutrient grower it shows how what they are feeding their plants can react if given in too high of concentrations. :peace:

 

Username85

Well-Known Member
If it's at the top only it's just a bit strong on the lighting, if it's all over its slight nute excess but what I see on your plants I wouldnt change anything yet. It's too close to perfect and may grow as is no changes.
Yeah I’ve only noticed at the top of the plant, could make sense why that’s the only one affected since it’s a good 2” taller-I actually raised my lights by 4” last night so hopefully that takes care of things-I’ll just keep an eye and make sure to back off nutes further
 
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