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Cal ,mag deficiency ??  

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Points: 179
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Hi , those are fastberry auto in 26 l coolbox dwc

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, 5th week starting , pH 5.97 , ppm 900 I suppose ppm need to be raised as it started to fall , currently stands 785 . I've only recently started adding calmag a week ago. Should I raise ppm to 1000 ? Are those spots and wrinkled/ twisted leaves are signs of calcium/magnesium deficiency ? I'm using an pH perfect MGB series , as they chart is completely useless ( burned two plants b4 ) I'm mixing my nutes per readings , what do you guys think about not changing the reservoir for full flowering stage(only top up with full strength solution , as it may be hard to take them out of the growbox) ??? . Any help highly appreciated 

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Joined: 7 months ago

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Points: 1990
Posts: 178


I am not an expert by any means, a few things that have helped me out:

Res temps should stay below 72f, ideally 66-68, didn’t see any stats on res temp, has caused me all sorts of issues and is often overlooked.

I used to feed as per charts, but staying at 50% max of recommended has done wonders for my recent plants. Had a hard time with it at first, more nutes meant bigger buds, but not so much. Quickly found out that less is more, keep them a little hungry. Have noticed the grows go smoother, less problems. 

Keeping ph at or slightly above 6 has been really good too, especially for calmag. Start with RO water, add calmag until ppm is around 150-200, then 50% of whatever nutes you using. Rarely do I go over 750 ppm, and if using led lights, calmag will definitely need to be upped.

Thinking the c02, rh, temps, light intensity/spectrum etc, have to be spot on to reap the benefits of pounding the nutes above 1000. 

Last note, would strongly urge you to continue changing res throughout all stages, go 2 weeks at the most. You could end up with a mysterioso mix and have no idea what’s in the 1000 ppm of solution. Lock outs, unstable ph, etc could all be problems that hinder a good harvest. Would recommend having a way to change out res even if buckets can’t be moved, or lids taken off. 

Hope some of this helps, and I’m sure one of the more experienced members can help you with diagnosing your problem. Thought I would share what has helped me out, but by no means guarantees results lol. 



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February 22, 2020