Defiency, nute burn, heat stress? Not sure what’s happening here

[MrMackey]

hi guys I’ll give you as much info as possible I know this setup is not perfect at the moment.

There in alien easy feed system with canna professional coco ph is set at 5.7 but rises to 6.5 every 2-3 days before reset. The ec is around 2.2 (tap water is 0.4) 0.3 is of cal mag then iconic bloom to around 1.9 some pk9/18 and meta boost these pics are of week 7 and I have a few in week 5 starting to go the same way.
600w gavitas 2-3ft above canopy sealed room set to 26 day 20 night humidity is 55-65% co2 1100ppm another thing I’ll add is the air circulation is not great at the moment although the opticlimate pumps a lot of air it’s not position well and in a large room at the moment (canopy temps could be a little high because of this)

Any ideas what’s happening here?
Thanks in advance

 

[Mr. Krip]

hi guys I’ll give you as much info as possible I know this setup is not perfect at the moment.

There in alien easy feed system with canna professional coco ph is set at 5.7 but rises to 6.5 every 2-3 days before reset. The ec is around 2.2 (tap water is 0.4) 0.3 is of cal mag then iconic bloom to around 1.9 some pk9/18 and meta boost these pics are of week 7 and I have a few in week 5 starting to go the same way.
600w gavitas 2-3ft above canopy sealed room set to 26 day 20 night humidity is 55-65% co2 1100ppm another thing I’ll add is the air circulation is not great at the moment although the opticlimate pumps a lot of air it’s not position well and in a large room at the moment (canopy temps could be a little high because of this)

Any ideas what’s happening here?
Thanks in advance

That is a phosphorous deficiency most likely due to your PH getting to 6.5 but possibly some other issues.

I'd let PH get as high as 6.0, then PH down to about 5.5 and let it drift back up. Max PH for P to be absorbed by cannabis in hydro is 6.2.

Also, I would do a flush of the medium. An excess of other minerals, like zinc and iron, can cause a P lockout, so the flush should take care of that.

You said you're using tap water. You may not need to add cal-mag, at all, with tap water although it would be needed with R/O. The Cal-Mag also has iron in it.

I hope that helps!



K

 

[MrMackey]

That is a phosphorous deficiency most likely due to your PH getting to 6.5 but possibly some other issues.

I'd let PH get as high as 6.0, then PH down to about 5.5 and let it drift back up. Max PH for P to be absorbed by cannabis in hydro is 6.2.

Also, I would do a flush of the medium. An excess of other minerals, like zinc and iron, can cause a P lockout, so the flush should take care of that.

You said you're using tap water. You may not need to add cal-mag, at all, with tap water although it would be needed with R/O. The Cal-Mag also has iron in it.

I hope that helps!



K

Thanks a lot for taking the time in this detailed reply mate I’m guna give it a quarter strength flush today and see how we get on I do usually keep the ph in range but had helpers looking after it while I was having an operation and they was struggling

Thanks again