Brown Spots

[Jamers]

Any suggestions on what this might be?
The plants are generally healthy but starting to see these spots

Cal deff??

PH was 5.6 when we changed the res last night but has floated up to 6.2 over night probably from chlorine?
day 1 flowering
RH 55-60%
Temps 23-24 C
PPM 550
DNF Veg Nutes
Cal Mag at half dosage
Dutch Masters gold range root zone at 8ml/20L
Water temps 68
Feminized Northern Lights
1000W DHPS at 50%
RDWC

 

[Chillenn]

Looks like it could be calcium, CalMag!

 

[AcesFull]

Are you starting with R/O or tap? If tap, what's the PPM before you add anything?

If R/O, what's the PPM after you add half strength cal/mag and before you add anything else?

These answers will help solve your problem.

 

[Jamers]

We are using filtered tap water
PPM before we add anything is 200

Sorry I didnt take a measurement of the PPM of the water with just the cal mag, i added my nutes then cal mag then measured it
Im guessing thats not the best method tho hah

Next res change ill check the ppm of just the water with cal mag

 

[CannaVince]

It's definitely a magnesium def.....cal/mag her....word...

 

[AcesFull]

The cal/mag should be the first thing you add so you know what your starting PPM is (before nutes).

We add cal/mag to R/O so we can mimic a 'good' tap water starting point. Since your tap is coming out filtered at 200, I have to believe there's lot's of cal/mag in there already. You should try to find a water report for your area. City governments have them on their websites.

If the majority of that 200 ppm is cal/mag, then I would definitely not add more. You could have too much and one is locking out the other. I forget the details off the top of my head, but too much is a bad thing.

I have a starting point of around 150-170ish ppm. My tap comes out at 110 and I add a touch of cal/mag to get it that high. I've never started at 200 or in your case probably much higher.

I believe you have a deficiency, but I strongly believe it is because something is being locked out, so it's stuck in the medium.

Good luck and keep us posted on your progress with the problem.

 

[Jamers]

Did a res change last week but forgot to measure the ppm before, ooops
Upped the ppm to 980 and tried to keep the PH in check spots seem to be the same not getting better.

Doing another change today
Getting 100-150 ppm of just water, Im useing a truncheon so the numbers aren't exact
Also Should i Be using EC x 500 or EC x 700 ?
This is based on EC x 700?

Added
30ml cal mag (1/4 strength) PPM 150
30ml cal mag
60ML Total PPM 200

Nutrients
210ml PPM 850
180ml
390ml Total PPM 1120

PH 6.8
19 ml total PH Down PH 5.6

Water Temp 56 C

Im going to let the water sit for a bit and see what happens
Hopefully this will help

They look fairly healthy overall which is nice
Any tips on trimming? got a lot of foliage

[

 

[kaption]

Did you correct the problem? was it cal/mag? Im having the same problem with my water.
Comes out of the tap at 200 , drops down to 170-180 within 24 hrs. I stopped adding cal/mag and my old growth started to yellow and new growth started to curl under. Think it might have been a nitro + cal/mag combo. I only had a few leaves with spots but they didnt look quite like that.

Only a few leaves got this bad tho.
Still havent corrected my problem, Still think it could be from not enuff nutes or when i stopped using cal/mag

 

[Jamers]

Let the water sit over night (in the dark of course)
And PH has drifted up to 5.8
Going to add some PH down and do the change



So far no we have not fixed the spots however we only upped the PPM to 960 on our last change so we may still be too low.
We ll see what happens over the next couple days with the ppm up higher

 

[Jamers]

Brown Spots do not appear to be getting any better

Now we have another problem
After 2 days PH went way up to 6.4 then dropped down to 4.4
PPM is un changed

On set of root algae?

Any suggestions ??