Is this common during transition?

Hello everyone, I’m growing a Mazar Kush Feminized non-auto. She’s in her first week of transition. Is it common to have some rust on the leaves? Can I still trim a few fan leaves off at this time? Overall she looks healthy especially around the bud sites.



Could be nutrient burn


Just went through a similar problem (my pH was too low, locked out all the nutrients) Looks like calcium deficiency, but…Suggest opening a ticket with the Grobo team :slight_smile:

(I can’t share links, remove the spaces)

www. growweedeasy. com/cannabis-symptoms-pictures

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Do you know if it’s safe to move the Top of the water tank to take a Ph reading?

I purchased a cheap digital pH reader for $16 CAD. It did the trick until my pH probe arrived (my issue was me: did not clean/replace pH probe at beginning of grow.)

Stephen did enforce that these cheaper pH readers lose their integrity/accuracy fairly quick, but it was an economic solution to monitor the pH level.

They say the roots dislike light, opening once to take a reading won’t do any damage.

I have a nice one but unfortunately I just realized the batteries are dead.

I put in a ticket to support.

What did you end up having to do?


For my situation: (still in late Veg)

I balanced my pH prior to fill using the digital meter. However, this was a temporary solution, as when the machine tried to add “nutrients”, it sent the pH out of wack. I removed both bottles 1 + 2 to stop the machine from sending the pH to 3.0 (because the probe was dirty, it assumed a 14.0 reading and would constantly unload bottle 2 (ph down).

I kept in close contact with Grobo Support for all my steps

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Just drain some of the water into a bucket and refill with same water once your reading is done.

The only problem is that the machine will add nutrients to the new fill each time.

They only add nutrients if you do a complete drain and fill.


Ah! I wish I knew that four weeks ago!! :rofl::rofl:


While I was taking the probes out I realized the pump wasn’t working. Mine is very quiet so I didn’t notice. Fortunately I got a back up pump when I got the Grobo. I just hooked it up and it’s working. I did have to lift the lid a bit high just so I could visually inspect the probes and they were clean. No gunk.

I just worry now that I exposed the roots too long.

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Should be fine as long as you aren’t peeking often.

I just did another drain/fill and put in some H2O2 hoping that the roots will get some much needed oxygen.

You put it in with the nutrient water? I’ve only tried soaking the roots with hydrogen peroxide and water in a separate container, keeping the lid on, and then returning it to the reservoir when the roots look saisfactory.

My understanding is that H2O2 kills good bacteria as well as the bad. I’m not sure about how it interacts with the nutrients tho, hope you checked that out beforehand!

According to my friend at the local grow shop you can use it and it will not mess with Ph or nutrient dosing. He’s been growing in hydro and soil for over 20 years and I trust him. He also mentioned that it’s better than hydro guard. I use it almost every water change since the roots took off. I generally use only the minimum it this time I used the max dose.

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Good to know!

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