Brown spots

[BAMWW]

Hi All,
Any idea what might cause these little brown spots? They are on a few leaves.
I'm using biotabs but I put them in the soil before planting and suffered some N toxicity early on.
I never added any other nutes but did use some cal-mag and power roots in the last two waterings.
The problem doesn't seem to getting any worse for now but I'd like to identify it all the same, it's my first grow in a new setup and her companions haven't faired out the best for multiple reasons so want to look after this one

I was thinking calcium or maybe phosphorus?
I think I should add a PK booster in flower but I don't see any info on when this should be done.


-Problem: Brown "rusty" spots on some leaves

-Medium/grow method: Soil

-Feed and supplements used: Biotabs. Used Plagron roots and some cal/mag for the last 2 waterings

-Water source: RO water

-Strain and age: FastBuds Orange Sherbet @ day 35(ish)

-Climate:Temps kept at about 25C. Humidity average of 45-55%

- Light used: LED COB about 9" from

-Additional info: The spots are small and probably nothing to be too concerned about but I had some N toxicity early in the grow as well.

 

[Mañ'O'Green]

Why did you add Cal-Mag. Now you have too much Ca or Mg! The other thing is you should never add nutrients to the pot out of balance which is what you did. When Cal-mag is actually needed - almost never! - It should be part of a complete nutrient blend.

 

[BAMWW]

I think I read that Cal-mag is needed when using RO water. So much conflicting info on the internet
To be fair I only used it twice and ay half strength so hopefully it doesn't do too much harm.


I was surprised by the Biotabs causing N toxicity too until I read on here somewhere they shouldn't be added until week 3. It doesn't say that on the instructions. I only used RO water to that point and the soil was lightmix so it couldn't have been anything else.

On the induced deficiencies chart you posted above, what does excess N cause?

Thanks for the reply

 

[Mañ'O'Green]

I think I read that Cal-mag is needed when using RO water. So much conflicting info on the internet
To be fair I only used it twice and ay half strength so hopefully it doesn't do too much harm.


I was surprised by the Biotabs causing N toxicity too until I read on here somewhere they shouldn't be added until week 3. It doesn't say that on the instructions. I only used RO water to that point and the soil was lightmix so it couldn't have been anything else.

On the induced deficiencies chart you posted above, what does excess N cause?

Thanks for the reply

It depends on what kind of soil and how it has been amended as to weather you would need calcium because of using RO. Most soils should have plenty. Now in hydro yes, you should add 50 PPMs of Calcium before you start adding nutrients, This is not true for all nutrient lines so read the instructions from the vendor.

Bio-Bizz lightmix is precharged and somewhere in the middle of soil or hydro? People miss the PH at 6.3 part. Bio-Tabs are high in nitrogen so yeah the combo could be too high in N.

To answer your question:

 

[BAMWW]

It depends on what kind of soil and how it has been amended as to weather you would need calcium because of using RO. Most soils should have plenty. Now in hydro yes, you should add 50 PPMs of Calcium before you start adding nutrients, This is not true for all nutrient lines so read the instructions from the vendor.

Bio-Bizz lightmix is precharged and somewhere in the middle of soil or hydro? People miss the PH at 6.3 part. Bio-Tabs are high in nitrogen so yeah the combo could be too high in N.

To answer your question:
View attachment 1278755

Thanks for that, especially the diagram. It does a good job of explaining the antagonistic action of nutrients

It's Plagron light-mix I'm using. Website says it contains enough fertiliser for one week but not a lot of other info on micronutrients.
I've been checking my PH and water in/out has been in the 6.3 - 6.5 range.

I had huge problems in my previous grows (different home, different setup). I think a lot of it was PH problems and water quality causing lockouts.
I recently had my water tested and hardness was 420ppm! That's a lot of calcium and would also cause PH issues if what I'm reading is correct?

My new setup has greater control of environment and I've access to both RO water and rain water so fingers crossed I have better luck
It got off to a rocky start while I got all the equipment working but it seems to be progressing well. Any issues I had I feel I correctly identified them and sorted it out. These spots were confusing me a little though!!

 

[Mañ'O'Green]

Thanks for that, especially the diagram. It does a good job of explaining the antagonistic action of nutrients

It's Plagron light-mix I'm using. Website says it contains enough fertiliser for one week but not a lot of other info on micronutrients.
I've been checking my PH and water in/out has been in the 6.3 - 6.5 range.

I had huge problems in my previous grows (different home, different setup). I think a lot of it was PH problems and water quality causing lockouts.
I recently had my water tested and hardness was 420ppm! That's a lot of calcium and would also cause PH issues if what I'm reading is correct?

My new setup has greater control of environment and I've access to both RO water and rain water so fingers crossed I have better luck
It got off to a rocky start while I got all the equipment working but it seems to be progressing well. Any issues I had I feel I correctly identified them and sorted it out. These spots were confusing me a little though!!

Wow that 420PPM water is horrible! You do not even want to drink that. What you could do to save water is mix it 1 gallon of tap water to 4 gallons of RO. This will save a couple of gallons of waste water. That is going to be very hard on the RO system membrane as the calcium is so high. It might be worth it to put a water softener in front of the RO system.

Bio-tabs are fairly high in N? I have never used them because I think of it as a shortcut effort at organic.

Now for something I just learned. Plagron says to RINSE ALL-MIX BEFORE USE. because it is too hot for new plants and not to fertilize for 6 weeks!

Now to try to remember this for the next unsuspecting grower.

Then there is the light Mix.

 

[BAMWW]

Wow that 420PPM water is horrible! You do not even want to drink that. What you could do to save water is mix it 1 gallon of tap water to 4 gallons of RO. This will save a couple of gallons of waste water. That is going to be very hard on the RO system membrane as the calcium is so high. It might be worth it to put a water softener in front of the RO system.

Bio-tabs are fairly high in N? I have never used them because I think of it as a shortcut effort at organic.

Now for something I just learned. Plagron says to RINSE ALL-MIX BEFORE USE. because it is too hot for new plants and not to fertilize for 6 weeks!

View attachment 1278954
View attachment 1278955


Now to try to remember this for the next unsuspecting grower.

Then there is the light Mix.

View attachment 1278961

I don't actually have my own RO system yet. I've been using water from work and supplementing with rain water when the weather permits. To be fair, the weather here is very suitable for the collection of rainwater - I just need to hook up a collection tank when outdoor gardening season kicks off in a month or two.
I already have a water softener so at least the RO filters may last a bit longer when I get around to installing one.
This is a bit off topic but...there is an argument to be made against the drinking of highly purified water as it supposedly pulls nutrients/minerals from your own body. Now I haven't researched this yet but it sounds like something that could be true. I wonder is this also the case for plants??

The info you shared above on the Plagron soils is very interesting, I didn't see that myself on the Plagron website. I always thought I could put germinated seeds straight into that soil. No wonder the last few seedlings struggled - between adding the Biotabs when filling the pots and putting seeds straight into the Lightmix, the soil must have been way too hot.
Here is the proof - the two plants in the pic below were planted on the same day. The one on the left is in the soil with biotabs and the one on the right is coco/perlite mix. This is my first attempt at coco and I'm VERY impressed so far! Both plants are Fastbuds Blackberry at day 18:

 

[Mañ'O'Green]

I don't actually have my own RO system yet. I've been using water from work and supplementing with rain water when the weather permits. To be fair, the weather here is very suitable for the collection of rainwater - I just need to hook up a collection tank when outdoor gardening season kicks off in a month or two.
I already have a water softener so at least the RO filters may last a bit longer when I get around to installing one.
This is a bit off topic but...there is an argument to be made against the drinking of highly purified water as it supposedly pulls nutrients/minerals from your own body. Now I haven't researched this yet but it sounds like something that could be true. I wonder is this also the case for plants??

The info you shared above on the Plagron soils is very interesting, I didn't see that myself on the Plagron website. I always thought I could put germinated seeds straight into that soil. No wonder the last few seedlings struggled - between adding the Biotabs when filling the pots and putting seeds straight into the Lightmix, the soil must have been way too hot.
Here is the proof - the two plants in the pic below were planted on the same day. The one on the left is in the soil with biotabs and the one on the right is coco/perlite mix. This is my first attempt at coco and I'm VERY impressed so far! Both plants are Fastbuds Blackberry at day 18:

That is the perfect example of what happens when the soil is too hot. Can you imagine it is like trying to stick your fingers in boiling water.

 

[BAMWW]

Just found this on the Biobizz nutrient schedule on their website:

I've stopped using it now anyway so I'll see how she recovers. I'm seeing what looks like P deficiency - I suppose this could be caused by the excess Ca from the calmag I added but it's only mild so far.

Can seeds germinated seeds be placed straight into Biobizz Lightmix?
I want to keep things simple and it seems Plagron Lightmix doesn't work well in this scenario.