Brown spotting on middle/upper growth, cal def?

[Skurge]

Hey guys, one of my four ladies has some brown spotting that started on the upper middle growth and spread upwards. I'm pretty sure it's cal def, but I'm a noob and want to be sure. Running four Dedoverde Haze and she's the only one showing any signs of deficiencies (she's also the biggest at around 29", two others are 26" and the smallest is 20"). The two 26" gals were also showing some discoloration early on, but it completely went away within a week of starting calmag (went up to 80% strength for a few days, using 1/2 strength as part of normal feed).

The spotting started around day 26-27, the plants were flushed and changed over to bloom nutes on day 29 (this is when I started calmag, post flush). Checked the PH (Pro Mix HP CC soilless mix) using the run off method, and it was around 6.1-6.2. Feed has been PH 5.7-5.8, but not too worried about it since I'm using AN PH Perfect. I'm 90% sure it isn't a PH issue since this is the only plant showing symptoms. No leaves have died off, but there's some crinkling on a few individual blades were the spotting got really bad. Most of her lowest growth (pretty much everything on the lower half) is still a solid healthy dark green with no spotting. Her bud development seems to be a little slower than the other three, but it's definitely there and I think she'll be okay. Just wondering if this is something to be really concerned about. They only have another 4 weeks or so to go.

She's currently on day 45.

Any help would be appreciated.

 

[Happy Horticulturist]

In my experience it looks like she's very low on calcium. In the next 4 weeks the situation will get worse and there's not much you can do to change it. Yes you can start feeding cal mag to her now and feed at full strength, or even a touch over. But it will take days to effect the plant and even then once she's gotten a good dose of calcium into her, she'll always look kinda sick like she does now and her buds will be smaller because of it. All you can do is next time as soon as you notice the very first sign of this happening hit her hard and quick with cal mag. Also at the beginning of flower feed half strength cal mag for safety to try and avoid this happening again, the moment you notice any cal issues go full strength.

 

[Skurge]

In my experience it looks like she's very low on calcium. In the next 4 weeks the situation will get worse and there's not much you can do to change it. Yes you can start feeding cal mag to her now and feed at full strength, or even a touch over. But it will take days to effect the plant and even then once she's gotten a good dose of calcium into her, she'll always look kinda sick like she does now and her buds will be smaller because of it. All you can do is next time as soon as you notice the very first sign of this happening hit her hard and quick with cal mag. Also at the beginning of flower feed half strength cal mag for safety to try and avoid this happening again, the moment you notice any cal issues go full strength.

Ok thanks, it's weird because they've all received the same treatment and she's the only one having this issue, maybe because she's a little bigger than the others and needed more. I actually started 1/2 strength cal mag a few days after the spotting started (at this point spotting was very minimal and it was mostly just discoloration), moved up to 80% for a few days and she never got better. Two others were showing slight signs of cal + mag def but improved within days.

They showed sex around day 15, but didn't get flushed and changed over to HPS + Bloom nutes until day 29 (this is when I started the 1/2 strength calmag). I just find it odd how she's the only plant that got cal def, even though she's the biggest, it's only by a few inches.

 

[elsamurai]

Ok thanks, it's weird because they've all received the same treatment and she's the only one having this issue, maybe because she's a little bigger than the others and needed more. I actually started 1/2 strength cal mag a few days after the spotting started (at this point spotting was very minimal and it was mostly just discoloration), moved up to 80% for a few days and she never got better. Two others were showing slight signs of cal + mag def but improved within days.

They showed sex around day 15, but didn't get flushed and changed over to HPS + Bloom nutes until day 29 (this is when I started the 1/2 strength calmag). I just find it odd how she's the only plant that got cal def, even though she's the biggest, it's only by a few inches.

I'd chalk that up to pheno type as a guess to why 1s need is different than the rest.