Powdery mildew around carbon filter, not on plants

I have found plenty of results on powdery mildew, but nothing about it being on something other than the plants. I am finding it on surfaces near the carbon filter. Power cords, tent walls, hanging chains, etc. My thoughts are that the filter is pulling all the humid air and leaving the moisture behind outside the filter, however, my humidity in the tent at mid level never exceeds 40% with an average of 30% @ 80F. I am about 4 weeks into vegging. Since day 1 I have misted the plants and tent walls 4 times to help boost the humidity so I don't think it's caused by spraying too much mist. I am using two Accurite indoor humidity monitors.

I live in PA. It's cold right now and my humidity would be 20% if I wasn't running a humidifier. I run it on full blast 24/7 and my humidity never goes above 40% at canopy level. It's a small 1 gallon vicks cool mist. I have a 6in 400cfm fan with a 6x16 Phresh filter. The tent is 4Lx2Wx5H. I am running the fan at full blast otherwise my temps exceed 85F. I have 2 passive flaps on the tent and 1 6in 240cfm booster fan blowing air into the tent through a 6in duct. The booster fan has a sheet of air conditioner filter over it. I have 2 clip fans in the tent moving air along with 4 85w CFL and a Blackstar 500w (300w actual) LED.

Stop misting and wash down with bleach water.

Would those few times of misting be enough to cause that? I will wash right now. Thank you!

Bleach, clorox whatever.

Yeah cannon, you really don't want that coming into play during flowering. i'd pull the plants out of the tent. use a solution of bleach and water, also put it into a bottle and mist your carbon filter. try to kill all of it if at all possible.

All cleaned. Leaving tent open for a bit to air out. From what you have gathered reading my post, do you have any suggestions for my setup? Here are some of my girls. They have light symptoms of something. It almost looks like nute burn. They just had there second dose of big bloom Sunday. I used 1.5tsp each time. I used plain soil with 0 nutrients. I only see this on 3 out of the 14 plants.

If it was growing on something other than a plant, it was not powdery mildew. It was some other type of fuzzy white fungi (there are many). Probably best to clean it up anyway. I'd try without the humidifier if I were you (especially during bloom).

SpicySativa said:

If it was growing on something other than a plant, it was not powdery mildew. It was some other type of fuzzy white fungi (there are many). Probably best to clean it up anyway. I'd try without the humidifier if I were you (especially during bloom).

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Wont humidity levels below 30% cause problems though? It dries up so quick in there with the exhaust sucking the hot air out.

I live in pa too. Same shitty weather. I haven't had any problems with mold yet tho. I have a 1 gallon humidifier in my grow closet but only run it when the lights are on. Try that. Humidity without the humidifier is 30-40% when lights off and 50-62 % when I run it with the lights on. When I don't have my lights on while my humidifiers running it goes up to 70+%. That's definetly a great place for mold to start. So try to put that humidifier on a 18/6 cycle or whatever your light cycle is an see how that does. Let me know

I agree coho

Pass420 said:

I live in pa too. Same shitty weather. I haven't had any problems with mold yet tho. I have a 1 gallon humidifier in my grow closet but only run it when the lights are on. Try that. Humidity without the humidifier is 30-40% when lights off and 50-62 % when I run it with the lights on. When I don't have my lights on while my humidifiers running it goes up to 70+%. That's definetly a great place for mold to start. So try to put that humidifier on a 18/6 cycle or whatever your light cycle is an see how that does. Let me know

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Thank you very much! I appreciate the tips! I just started 18/6 yesterday so I just plugged the humidifier into that strip. I will keep an eye on things.

Do you have any thoughts on the condition of my plants in the two photos?

No problem that's what we're here for. I would suggest this link. https://www.icmag.com/ic/showthread.php?t=11688

Greetings! All is well here.

I think I have an idea on the white dust. It is common for the humidifier I own... the Crane Drop.

http://crane.harmonyapp.com/customer-care/drop-humidifier-faq/

CanonEOS said:

Wont humidity levels below 30% cause problems though? It dries up so quick in there with the exhaust sucking the hot air out.

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30 percent humidity is favourable in flower. it will prevent the risk of bud rot. also some minor nute burn but nothing to worry about.

Pass420 said:

No problem that's what we're here for. I would suggest this link. https://www.icmag.com/ic/showthread.php?t=11688

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So I lowkey have run into the same problem but I think mine looks slightly different than his! My exhaust fan and filter have like a white powder on it kind of like a chalky texture, its not on the plants, but it is on my strings hanging up, and you can see it on top on the light, and some of my 4inch fans as well! My temps are around 75-77 and my humidity is usually 45-55%. I live in Las Vegas so it is very hot and very dry, I mist the plants everyday, Im growing in Organic soil, any idea on what this could be? Is it normal I should I fix it if possible

Stoned Gentleman07 said:

So I lowkey have run into the same problem but I think mine looks slightly different than his! My exhaust fan and filter have like a white powder on it kind of like a chalky texture, its not on the plants, but it is on my strings hanging up, and you can see it on top on the light, and some of my 4inch fans as well! My temps are around 75-77 and my humidity is usually 45-55%. I live in Las Vegas so it is very hot and very dry, I mist the plants everyday, Im growing in Organic soil, any idea on what this could be? Is it normal I should I fix it if possible

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The white powder is from your humidifier... I can't believe all the data available on the web for growing and this issue is rarely discussed. This white powder is calcium from the water in your humidifier and also remember not only will it clog your carbon filter but the powder gets everywhere else in your tent, you just can't always see it. The extra minerals are also getting in your plants and it took me a couple grows to figure this out.

I just ordered some Demineralization Cartridge Filters from Amazon...you can also use Distilled Water only in your humidifier.

Trust me, this is your problem and the fix.

That70sDude said:

The white powder is from your humidifier... I can't believe all the data available on the web for growing and this issue is rarely discussed. This white powder is calcium from the water in your humidifier and also remember not only will it clog your carbon filter but the powder gets everywhere else in your tent, you just can't always see it. The extra minerals are also getting in your plants and it took me a couple grows to figure this out.

I just ordered some Demineralization Cartridge Filters from Amazon...you can also use Distilled Water only in your humidifier.

Trust me, this is your problem and the fix.

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While I agree
He hasn’t been on in two plus years

Still fighting pm lol

That70sDude said:

The white powder is from your humidifier... I can't believe all the data available on the web for growing and this issue is rarely discussed. This white powder is calcium from the water in your humidifier and also remember not only will it clog your carbon filter but the powder gets everywhere else in your tent, you just can't always see it. The extra minerals are also getting in your plants and it took me a couple grows to figure this out.

I just ordered some Demineralization Cartridge Filters from Amazon...you can also use Distilled Water only in your humidifier.

Trust me, this is your problem and the fix.

Click to expand...

Thanks for the alpha on demineralization cartridges. Just ordered some for my ultrasonic humidifier. The white dust is frustrating!

That70sDude said:

The white powder is from your humidifier... I can't believe all the data available on the web for growing and this issue is rarely discussed. This white powder is calcium from the water in your humidifier and also remember not only will it clog your carbon filter but the powder gets everywhere else in your tent, you just can't always see it. The extra minerals are also getting in your plants and it took me a couple grows to figure this out.

I just ordered some Demineralization Cartridge Filters from Amazon...you can also use Distilled Water only in your humidifier.

Trust me, this is your problem and the fix.

Click to expand...

For what it's worth, thank you for bumping this post, I'm sure it's the only reason I found it on Google search lol.

Completely green to growing, this white powder has been freaking me out assuming its PM but was never on the plants, just the walls, fans, carbon filter sock etc. Really glad to see it's just my humidifier/crappy city water.

I appreciate you!