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Mildew: How to shut down and clean? Sulfur? Ozone?

MedResearcher

Member
Veteran
Can get UV lights to help. They sell units that have a fan that circulates the air passed a UV bulb to sterilize the air.

Fix the environment, add a UV light air treatment. Afaik hospitals use similar UV light systems to help sterilize the air.

Always been a fan of sealed grow rooms. If the AC and Dehuy are sized correctly, it is only a matter of adjusting the temps/RH/dialing it in so you never see PM again.


Mr^^
 

G.O. Joe

Well-known member
Veteran
You sure? It is carcinogenic, poisonous and explosive mixed with air or oxygen!

The IARC is in a word fraudulent and there is no evidence to support problems from low level exposure in humans, in spite of much such exposure in the 1900's. Formaldehyde is a metabolite and we have means to deal with it even though it does bind to DNA.

It is not a systemic or cumulative poison by inhalation in any amount you're likely to experience, even though your eyes and nose easily detect ppm.

It's true, the ACS monograph gave a 7% low end explosive mixture with air, but in practice problems seem to be pretty rare. For general sterilizing fumigation purposes the paraformaldehyde manufacturer recommends 0.3-0.6 g/ft3 heated to 400-475 F with an electric heater. The humidity is supposed to be 60-85% adjusted by boiling water if necessary - perhaps the explosive mixtures refer to dry air and monomer. They also say after 10 hours to heat 1.2-2.4 g/ft3 ammonium carbonate or 1.6-3.2 g/ft3 bicarbonate on a different heater turned on remotely to generate ammonia and convert the formaldehyde to hexamine in 30-180 minutes. The actual amount needed for just mold and mildew is probably less, as they appear to be sensitive to low levels of formaldehyde.

Formalin also has a long history of horticulture use. You might even be able to sterilize your grow medium with it, neutralize with a solution of urea, and get slow release fertilizer too.

Good thing I didn't mention methyl bromide, easily made by heating a mixture of water, methanol, sulfuric acid, and KBr or NaBr.
 

TanzanianMagic

Well-known member
Veteran
With no plants alive in room and I hit the walls hard with these compunds I am thinking a few days of shut down. 3 days? 7 days? what does everybody think?
Whatever you do to disinfect the grow room is a plus.

However powdery mildew is everywhere, and can in my opinion at best be displaced by other fungi.

Also, dealing with the environment is key - temperatures, humidity, airflow (ventilators - which should also be cleaned - pruning).

Bacillis subtilis eats mildew. Worm tea before flowering, stinging nettle extract, baking soda also work - before flowering.

Also, if you grow organically with decomposable carbon containing mulch (hemp bedding, straw) and add soft fruit like banana or oats underneath the mulch, then you are creating a very fungally friendly environment, and mildew should frankly seize to be an issue. There are fungi that grow throughout the plant called endophytes, and produce antibiotics, and the fact that they're made of pectin is an anti-feedant to insects. (By the way it are also the insects that track around the fungi, good or bad.)

Nature invented all this stuff millions of years ago, allowing forest to grow themselves without bags of nitrogen fertilizer, or dying from powdery mildew. It is only when we grow monocrops for the ease of harvesting, and don't return the carbon and seeds to the soil for the mycorrhizal and other fungi, that insects and hostile fungi get out of control.

I grow outside and I've had it all this year - mildew, mites, aphids, whitefly, caterpillars, however the plants just keep growing and never look back. I haven't poured or sprayed anything on them this year.
 

al70

Well-known member
I dunno much about PM, never had it thank jaysus, but i lost my last crop, 50 plants to but rot, fuckin sickened me, i've been told alcohol is the only way to get rid of it from the grow area, i could'nt get my hands on pure alcohol so i got two liters of poitin, which i have been told is 80% pure so i sprayed the whole place with it, what a fuckin smell, my neighbours must think i'm a chronic alcoholic, any way i'm setting up next week, i hope i got rid of it, and i hope you get rid of you're problem also, those fuckin spores can last for years i'm told, goodluck.
 

Guy Brush

Well-known member
ICMag Donor
Veteran
I dunno much about PM, never had it thank jaysus, but i lost my last crop, 50 plants to but rot, fuckin sickened me, i've been told alcohol is the only way to get rid of it from the grow area, i could'nt get my hands on pure alcohol so i got two liters of poitin, which i have been told is 80% pure so i sprayed the whole place with it, what a fuckin smell, my neighbours must think i'm a chronic alcoholic, any way i'm setting up next week, i hope i got rid of it, and i hope you get rid of you're problem also, those fuckin spores can last for years i'm told, goodluck.

That's crazy! One spark and you'll go bang!!! Besides that you won't get rid of bud rot that way. Better you should try to change the room climate or the strain or both!
 

al70

Well-known member
last year guy, spores i'm gettin rid of, i'm not gonna spark me bulbs up in that enviroment,i'll clear the enviroment before i start, ye remind me o me provo cousin, lol
 

PaulieWaulie

Member
Veteran
Budrot and PM are totally different beasts, no point mentioning it here really. Having said that Id take your budrot problem any day of the week over pm.



Also I was joking with the formaldehyde order, I have never heard of that and thought he was trolling so I trolled back.


UV lights help, to be honest, they don't sound like a solution
I think most people suggesting it haven't used it but simply read the marketing material out there that was created to sell the machine.

First off the machine is way overpriced at like 300$$ USD its a low wattage bulb in a reflector!
Second it needs to be done almost every single day
third it needs to be 2 inches from all plant material to be effective
fourth even on the website it says it doesn't eliminate but reduce overall by 80%.

So all in all I don't think it is part of an eradication process and is maybe best suited for cleaning air that is running through an intake filter so it is killing 100% of anything passing through the vent
 

G.O. Joe

Well-known member
Veteran
thought he was trolling so I trolled back.

And lastly formaldehyde as from heated paraformaldehyde or from formalin and permanganate has been the most used agent to completely sterilize biomedical rooms cabinets and hoods, considered safe with electrical equipment and less corrosive than other options. EPA and OSHA have been eroding use in the US but all sterilants are toxic and formaldehyde won't poison you if you don't get it in or on you, and your eyes will let you know if you're being exposed to an unsafe amount. There has been no human cancer shown to be caused by formaldehyde exposure, just like there is no increased cancer risk in Hinkley California, and I suspect in J&J baby powder users as well. Paraformaldehyde is sold for consumer use in Florida to prevent mold and mildew with ppm amounts of a monomer that inactivates viruses as well. Apologies for foisting such foolishness on this and all the other threads. PaulieWaulie, don't be fooled by my use of the word you, I don't write my posts solely for you. Logging my troll ass out.
 

redlaser

Active member
Veteran
I’ve never heard of formaldehyde as an option on any cannabis forum, only in ornamental horticulture. Might explain why it seems extreme to some. I have to admit I thought formaldehyde was more unsafe, thought I recall a leukemia possibility from formaldehyde treated furniture. It was a news story on tv in the last week.

G.O. Joe is a valued contributor, have yet to see him in troll mode
 

PaulieWaulie

Member
Veteran
And really I have greencure, Sulfur Burner, Eagle 20. + shutting down for 2+ Months with a complete clean & restart, + having fixed airflow/exhaust/RH. I am not a big time grower, just a small guy trying to learn to grow good weed. Spending above any beyond what I have is not justified or able to be paid for by any harvests in the near future. Im drawing the line. I have had it. If PM is the end of me so be it. It will be gods will.
 

TanzanianMagic

Well-known member
Veteran
I dunno much about PM, never had it thank jaysus, but i lost my last crop, 50 plants to but rot, fuckin sickened me, i've been told alcohol is the only way to get rid of it from the grow area, i could'nt get my hands on pure alcohol so i got two liters of poitin, which i have been told is 80% pure so i sprayed the whole place with it, what a fuckin smell, my neighbours must think i'm a chronic alcoholic, any way i'm setting up next week, i hope i got rid of it, and i hope you get rid of you're problem also, those fuckin spores can last for years i'm told, goodluck.
The best way to prevent budrot is to reduce the humidity or watering.

Weed is an tropical annual plant, it evolved to germinate in the cool wet season, thrive in the hot and wet season, and survive the hot and dry season.

The buds are basically designed to attract humidity from the air when temps are 40C and the relative humidity is 20%. And when whatever moisture there was in the soil is gone until the next monsoons.

The problem is that most people feed and water their plants at the same time. They have to water the plant when it goes hungry.

The way to go is to have a water reservoir at the bottom of the pot or bed, growrocks on top, supersoil, light soil, mulch to top it off. That way you can empty out the reservoir when the buds stacked and they're attracting more moisture than the leaves can evaporate. The plant can still feed by leading water back into the soil from the buds.

My point being, that when buds are mature, they actually attract humidity.
 
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