4.5 weeks into flower, small rust spots on some leaves. Cal/Mag?

Day 31 of flower, she’s coming along pretty well. Have some general necrosis on some of the oldest fan leaves. Some of the middle-aged fan leaves have started showing small rust spots.

I had this same issue with another plant(ended up being a male) during the veg cycle. I would like to figure out the issue to avoid it in the future. I’m thinking it could be a cal/mag issue. Any help is greatly appreciated. Should I just let it ride with only 3.5~ weeks or so until harvest?

FFOF soil/5 gal smart pot

FF trio nutes(have cut out Grow Big at this point), Herc Harvest, Aphrodites Extraction, Posedonzime, Fish Shit.

All nute water PH’d to 6.5~

I would feed cal mag if you have it, if not, you can let it ride. Just know your fan leaves will be scavenged, and will look a little rough.

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@Covertgrower Thanks for the reply. Cal/mag is something I haven’t invested in. Was hoping to get enough from the Herc harvest, other nutes and tap water. This is my first grow, so I’m mainly looking to identify the issue to avoid it in the future. Especially since I’ve had the same issue on a bigger scale with another plant in this same grow.

have you ever heard anything about mixing NFTG nutes with fox farms? i am trying to remember what i saw on the NFTG website videos and it escapes me.

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@pptrsha1 I haven’t. My thought is that NFTG tend to lean less synthetic and all of the ones I’m using specifically state that they can be used with other nutrients. Also, the plant that had a big problem with this issue earlier in the grow wasn’t being fed NFTG


thanks. i have both lines and was trying to remember what i saw

A lot of growers mix nutrient lines. As long as you’re aware of NPK adding together you can use different products together.

@Covertgrower are you inclined to say it’s most likely a Magnesium issue?

Calcium is my first opinion.

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thanks i kept thinking there was something i read

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