Brown / orange blotches and general unhealthy looking

Pretty new to coco and new shed setup, done one auto grow to dial in. Just finishing my first regular run, these are the clones of that run, in a 2.4x1.2m veg tent.

Before today I had forgot to change the bulb in the reflector from a 1000w HPs to 600w Mh, and had been running the 1000w dimmed to 600 for what I imagine is a very bad spectrum.

9 days ago potted up from 6l to 15L. The issues were there beforehand but I never paid too much notice and thought they’d come round with a pot up. Turned on the 630cmh along with the 1000w and spread them across the entire tent at this point.

They are on Canna Coco A/B, calmag, and rhizo tonic. I quite often use the leftover of my flower room mix, add water to reduce EC down to 0.8 - 1.0. Could this be my issue? Wasn’t doing this on last few runs.

The smaller plants down the side are the same clones but held back in 1l pots for the run after. They are darker green and healthy with non of the issues. I don’t understand why.

thanks for reading

Looks like magnesium deficiency to me since the leaves are yellowing from outside in at the same time as the rusty spots are appearing and it's hitting leaves all over since magnesium is mobile.

How much calmag per litre have you been using?
What's your pH ?
What temps (lights on and off) ?
What humidity (lights on and off) ?
How high above canopy are the lights ?


Cheers.

plantastic said:

Looks like magnesium deficiency to me since the leaves are yellowing from outside in at the same time as the rusty spots are appearing and it's hitting leaves all over since magnesium is mobile.

How much calmag per litre have you been using?
What's your pH ?
What temps (lights on and off) ?
What humidity (lights on and off) ?
How high above canopy are the lights ?


Cheers.

Click to expand...

Thanks for the reply

Magnesium makes sense. I never thought about it, but with me diluting down my excess flower feed for the veg room, from 1.2-1.8EC, down to 0.8-1.0, it is not only the A/B being diluted, but the calmag. Which in coco they seem to want lots of full cycle.

Around 4-5ml calmag per 10l. This takes EC to 0.4, I am in very soft water area. EC often too low out of tap to even register the 0.2 on my truncheon.

Ph 5.8-6.2, typically 6.0.

Currently on 24 hour lights since pot up to maintain temps without huge heating bill. Another 2 weeks like this til move to flower room for final veg and flip. Symptoms were showing before pot up when they were on 18/6 though.

19-24C temps as day/ night outdoor temps change.

70-90% humidity sadly. Super high here this time of year.

Lights about 36” above canopy.

I will stop diluting down my flower feeds for the veg room straight away. Sounds like a bad idea now I have thought about it more, even if this isn’t mag deficiency.

Environment seems fine except for the high humidity, but that's only a concern in late flower really. I would dial up the calmag to 1ml/L every feed and yes the dilution probably isn't helping.

Let us know how it goes

plantastic said:

Environment seems fine except for the high humidity, but that's only a concern in late flower really. I would dial up the calmag to 1ml/L every feed and yes the dilution probably isn't helping.

Let us know how it goes

Click to expand...

1ml / L sounds awfully high, would expect that to put me upto 0.6ec or so before A/B but I’ll give it a shot and test and see how it goes!

thankyou for the replies