Hydro - weird yellowing on new growth

[vick]

View attachment 205605

Posted this up in my log, but thought it would serve a better purpose here as well, if anyone else ran into this problem..

Never seen anything like this before. This is a blue mystic on day 17. The res is well aerated with a current ph of 5.5 and 480ppm. Res temp is 66f

My ph did swing up to 6.0 the night before this happened, so I just fixed it before taking this picture.

Any thoughts?

 

[kfigerm]

Hi,

I'd check/calibrate the ph-meter, seems some N lockout due to ph...imo too sour.
But I did dwc only once, so please wait for other thoughts on this.

Cheers & good luck

 

[Groff]

I've just had the same thing happen to me. Was feeding at pH 5.8 (in coco), calibrated and lower to 5.7, seemed to do the trick. If it persists, I would immediately add a small dab of Cal Mag

 

[OOOGaUtO]

Yoooo whats up Vick, my Cheese Berry from my current/only run, remember my CB was showing strong signs of late cal/mag def around day 10 more calcium def than mag tho. I went to the diagnose your plants thread heres the link https://www.autoflower.org/f74/self-diagnose-your-plants-basic-deficiencies-list-11.html

My new growth on CB around that time looked exactly the same, mine had purple hues showing in the dead center with new growth and as that grew the purple hue faded to and the light green was showing like yours. I added cal/mag and everything got better altho i see some of the light yellow here and there especially after like 5 or 6 days of same res and then i change it and give her some fresh water and nutes....i assume that they must eat all the cal/mag and need more.......maybe

Hope this helps and ur babies are really taking off! good healthy lil ladies karma sent ur way

 

[vick]

As I've been told, the ph-80 HM meter I have comes factory calibrated to 7.0 but I will go ahead and check it tonight to make sure. Better be safe than sorry right? I'll see how she reacts with the ph swing being fixed and if she's still like this tomorrow, I'll wait until my weekly res change on saturday. I'll add 5ml of cal/mag per gal this time instead of 2.5 and will report the changes in this log as well. Thanks for the grow karma and the advice! +REP to you all.

 

[vick]

Happy to report that the above plant is now back on par after a ph adjustment. Def gotta keep that res under 5.8. The yellowing is all green and she's lookin great. Thanks again.