What can cause red streaks up stalks in coco?

[indica4mymeds]

I use coco and I've used several different nutes on each grow with at least 8 phenos,4 different strains.
I didn't have this issue with soil or soil/coco but only with coco/perlite and it keeps reappearing so soil provides something coco doesn't.
It always happens during mid to late bloom.
1st the channels in stalks turn radish red,then as time goes on the stalk as a whole turns radish red.
It happens with both leds and t5.

 

[BrodyNitro]

Usually a phosphorus deficiency if it's not from colder temps. I've got one vegging right now with some streaks because I thought my nutrient solution's pH was lower than it was and P was getting locked out (had to back down since I was starting to see nutrient burn and figured pH would still be an acceptable level). Ten drops/gal of pH down and the streaks are already starting to fade

 

[arellanobrian]

mag deficiency can cause purpling of the stalk and leaf stalk/veins, you can get some Epsom salts for cheap at any dollar star and mix with plain water in a spay bottle for a foliar feeding. foliar feeding gives the plants quicker access so you can see results faster

 

[sonicDlf]

If you are growing with led you will find that you need to add cal/mag from about week 3 .
Be safe .

 

[Stoney Roads]

I have one I just moved from soil to 100% coco and today it is got purple leafs stems. I assume because coco has no calmag and I took all the soil from off the roots so there is no soil in with the coco

 

[glimmergrass]

For me it was mag in vegetation -- added more calmag and all was well. Later on, in flowering, it was because the room was pretty cool Stalks, leaves turned purple/red!

 

[arellanobrian]

yes usually while they are washing the coco of salts the coco has a tenancy to absorb mag and potassium to replace the salts that were rinsed out, then releases it later in flower so adding cal mag at least in veg in necessary, also is why alot of companys have a special nute for coco.