Fungus gnats? Help!

f-e said:

Fungus flies are not thought to effect growth. Even in pure hydro where the only thing to eat is soaking wet roots, they're not blamed for plant health issues as they don't choose to eat the plants.

There is some damage on a leaf or two where something has been sucking the sap out. That is likely a different pest, that may of been just passing through. The sticky traps are very useful in this instance.

There might be a bit of Mg and P deficiency showing. Stalled plants generally respond to some P so I would start there. Perhaps a lick of flower food or PK if you don't have a mono P source available. Bonemeal might be the organic option, I'm not sure but someone will chip in

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mimistow said:

Hello guys ,Im growing under a 180W led light ,plants are 45 days old .In some point i introduced some strawberry plants and some herbs to the indoor garden to fight off the smells but a week after i watered all of the plants i saw flying bugs in the enviroment. ? was thinking that they are just some regular small flies but after a small period of time my kids started to get droopy and overwatering or underwatering wasnt the issue.I ve never encounter any bug issue so im completely clueless of whats going on.Any help or advise would be very appreciated.Thank you for instance!
The first photo is a taken 17/11 ,the second one 24/11.the third 25/11 where at this point the plant to the right started to recover a bit considering that the leaves stood a bit upwards.The plant to the left got a pale green colour and the one in the center is somewhere in the middle.

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TanzanianMagic said:

There are several bugs on these plants:

1. The last photo shows damage more like that of a leafhopper.

2. The fungus gnats don't eat. It are their larvae that do damage. They are deadly to germinating seeds, and may cause some deformed roots in seedlings.

Thing is, if you grow in organics and have an organic mulch, there is always something else for them to eat, so they don't bother the plants as much.

A biological control for fungus gnat larvae are Steinernema nematodes.

When all else fails, you can mix water (a quart/liter), food grade/edible vegetable oil (1 tablespoon), dish soap (just enough the dissolve the oil into water) and add the recommended amount of drops of pyrethrin (usually 10 drops per quart). Pyrethrin is not good for you, however it is allowed in organic agriculture. It breaks down into non-toxic components in about a week. It was derived from the Chrysanthemum.

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Mattbho said:

Do get some yellow cards as stated , mosquito dunks and or nematodes . If this is not possible you have to block access to the medium via sand ,thick ass layer of perlite works ok .

Do not water plants until they are dry and weightless you want to almost have them droop before watering again . When battling the gnats i only bottom water the plants that need .

Also the 100 deg 10% rh is killing ya? ?

ARE YOU USING?

SOIL:


How long has this problem been going on?
What STRAIN are you growing?
What was the establishing technique? (seed or clone?)
What is the age of your plants?
How long have they been in the soil mixture they are in now?
Were they in the same mixture when they were seedlings/smaller plant? If not, what mixture were they in before?
How Tall are the plants?
What PHASE (seedling, vegetative or flower) are the plants in?
What Technique are you using? (SOG,*SCROG*etc)
What size pots are you using? (Include how many subjects to pot)
What substrate/medium are you using? What brand of soil mixture are you using?(percentage of perlite, vermiculite...etc?)
What brand Nutrient's are you using?
How much of each nutrient are you using with how much water? *Knowing the brand is very helpful*
How often are you feeding?
If flowering, when did you switch over to using Bloom nutrients?
What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd ect)
What is the TDS/EC/PPM of your nutrients used?
What is the*pH*of the "RUN-OFF"?
How often are you testing*pH/ppm/EC/TDS?
What method of*pH*test was administered? Using Strips?*pH*pen?
How often are you watering?
When was your last feeding and how often are you feeding?
What size bulb are you using?
How old is your bulbs?
What is the distance to the canopy?
What is your RH Factor? (Relative Humidity)
What is the canopy temperature?
What is the Day/Night Temp? (Include fluctuation range)
What is the current Air Flow? (cfm etc.)
Tell us about your ventilation, intake exhaust and when its running and not running ?
Is the fan blowing directly at plants?
Is the grow substrate constantly wet or moist?
Is your water HARD or SOFT?
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water?
If using tap water, what is the ppm/EC/TDS of the water right out of the tap?(Only if you have a tds pen)
If using RO,Distilled,mineral water, what is the ppm/EC/TDS without any additives?(Only if you have a tds pen)
Are you using water from a water softener?
Has plant been recently pruned, cloned or pinched?
Have any pest chemicals been used? If so what and when?
Are plant's infected with pest's?


HYDROPONICS/Aero Ponics/Coco/Soiless/

How long has this problem been going on?
Are you growing in a PVC grow tent? (example: Hydrohut or any other non brand tents)
What system are you running? (DWC? Ebb flow? Aero? Water Farm? Flood Tables? and so on...)
What STRAIN are you growing?
What was the establishing technique? (Were the seed or clone?)
What is the age of your plants?
How long have they been in there mixture they are in now?(coco,soiless etc..)
How tall are the plants?
What PHASE are the plants in? (seedling, vegetative or flower) are the plants in?
What Technique are you using?
What substrate/medium are you using?(Hydroton, RockWool etc.)
What is the Water temperature?
What color are your roots? White? Brown? Are your roots slimy?
What Nutrient's are you using?(If growing soiless)
How much of each nutrient are you using with how much water? *Knowing the brand is very helpful*
How often are you feeding? (If using soiless)
How often are you giving nutrients? (If using soiless)
If flowering, when did you switch over to using Bloom nutrients?
What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd ect)
What is the TDS/EC/PPM you are using
What is the*pH*of the "Tank"?
How often are you testing your*pH/PPM/EC/TDS?
Are you sure your calibration is correct on your equipment?
When was your last watering?
What is your water temps?
When was your last feeding change? (ie. grow-bloom-micro-additional)
How often do you clean your system: example: Flush out water replace with clean water and nutrients?
What size bulb are you using?
How old is the bulbs you are using?
What is the distance to the canopy?
What is your RH Factor(Relative Humidity)?
What is the canopy temperature?
What is the Day/Night Temp? (Include flucutaion range)
What is the current Air Flow? (cfm etc.)
Tell us about your ventilation, intake exhaust and when its running and not running ?
Is the fan blowing directly at plants?
Is your water HARD or SOFT?
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water?
If using tap water, what is the ppm/EC/TDS of the water right out of the tap?
If using RO,Distilled,mineral water, what is the ppm/EC/TDS without any additives?
Are you using water from a water softener?
Has plant been recently pruned, cloned off of or pinched
Have any pest chemicals been used? If so, What and When?

Click to expand...

Mattbho said:

Definitely scope the bottoms of the leaves believe it or not gnats are one of the larger pests.

View attachment 553300

View attachment 553301

And there is way smaller out there

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Switcher56 said:

Never, ever, ever, introduce something to your grow room that hasn't been quarantined 1st.

WHAT ARE FUNGUS GNATS?
Fungus gnats are tiny, dark, short-lived gnats that look like small flies. If you have an infestation, you will see them jumping around on the soil. Unlike some other cannabis pests, fungus gnats don’t have much of an interest in the leaves or flowers of your weed as they live in the soil. Instead, larvae gnaw on the roots and damage them. Since the root system is critical for healthy growth, a fungus gnat infection can be a problem.
Fortunately, fungus gnats are not the worst pests you can encounter. If you have mature plants with a strong root system, fungus gnats may be more of a nuisance than a catastrophe. On the other hand, they pose a serious threat to young plants and seedlings. A massive infestation left unattended can also be a problem for bigger plants.

https://www.royalqueenseeds.com/blog-how-to-stop-fungus-gnats-from-damaging-your-weed-plants-n345

I feel for you but I never experience the problem with cannabis, but I have with Bonsai. I do know however, you won't make that mistake again. The best way to reduce or eradicate smell is via a charcoal filter. The only time my tent smells is when the door is open for maint. I did follow a recommendation however (early in my growing adventure) to place a mint plant in there. It didn't do diddly, so to speak, so I quit the practice.

I am really anal wrt environmental conditions of my tents, right down to having HEPA filters on my "passive intakes". I wish you all the best

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Sunshineinabag said:

Well my first step would be sticky fly traps or tape put where they congregate......then try to cover your medium....IE size black plastic garbage bags to your pots.....strechy and tape over your mediums where your main stem pops up just make sure there no space for them to use....water your plants from below....they will absorb the water from an overflow tray for example over a small period if time. You do not need to top water plants

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TanzanianMagic said:

There are several bugs on these plants:

1. The last photo shows damage more like that of a leafhopper.

2. The fungus gnats don't eat. It are their larvae that do damage. They are deadly to germinating seeds, and may cause some deformed roots in seedlings.

Thing is, if you grow in organics and have an organic mulch, there is always something else for them to eat, so they don't bother the plants as much.

A biological control for fungus gnat larvae are Steinernema nematodes.

When all else fails, you can mix water (a quart/liter), food grade/edible vegetable oil (1 tablespoon), dish soap (just enough the dissolve the oil into water) and add the recommended amount of drops of pyrethrin (usually 10 drops per quart). Pyrethrin is not good for you, however it is allowed in organic agriculture. It breaks down into non-toxic components in about a week. It was derived from the Chrysanthemum.

Click to expand...

Switcher56 said:

The problem is that the OP never posted any informational data in what he was or is doing. Therefore anything we write is merely a guess.

OTOH, in early stages (I don't consider 45D, an early stage), the larvae will munch on your roots = dead roots. Sufficient dead roots in the root zone, combined with "perhaps" over watering or sodden soil and, you are setting up an anaerobic condition in the soil that leads to root rot.

Click to expand...

Mattbho said:

Do get some yellow cards as stated , mosquito dunks and or nematodes . If this is not possible you have to block access to the medium via sand ,thick ass layer of perlite works ok .

Do not water plants until they are dry and weightless you want to almost have them droop before watering again . When battling the gnats i only bottom water the plants that need .

Also the 100 deg 10% rh is killing ya? ?

ARE YOU USING?

SOIL:


How long has this problem been going on?
What STRAIN are you growing?
What was the establishing technique? (seed or clone?)
What is the age of your plants?
How long have they been in the soil mixture they are in now?
Were they in the same mixture when they were seedlings/smaller plant? If not, what mixture were they in before?
How Tall are the plants?
What PHASE (seedling, vegetative or flower) are the plants in?
What Technique are you using? (SOG,*SCROG*etc)
What size pots are you using? (Include how many subjects to pot)
What substrate/medium are you using? What brand of soil mixture are you using?(percentage of perlite, vermiculite...etc?)
What brand Nutrient's are you using?
How much of each nutrient are you using with how much water? *Knowing the brand is very helpful*
How often are you feeding?
If flowering, when did you switch over to using Bloom nutrients?
What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd ect)
What is the TDS/EC/PPM of your nutrients used?
What is the*pH*of the "RUN-OFF"?
How often are you testing*pH/ppm/EC/TDS?
What method of*pH*test was administered? Using Strips?*pH*pen?
How often are you watering?
When was your last feeding and how often are you feeding?
What size bulb are you using?
How old is your bulbs?
What is the distance to the canopy?
What is your RH Factor? (Relative Humidity)
What is the canopy temperature?
What is the Day/Night Temp? (Include fluctuation range)
What is the current Air Flow? (cfm etc.)
Tell us about your ventilation, intake exhaust and when its running and not running ?
Is the fan blowing directly at plants?
Is the grow substrate constantly wet or moist?
Is your water HARD or SOFT?
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water?
If using tap water, what is the ppm/EC/TDS of the water right out of the tap?(Only if you have a tds pen)
If using RO,Distilled,mineral water, what is the ppm/EC/TDS without any additives?(Only if you have a tds pen)
Are you using water from a water softener?
Has plant been recently pruned, cloned or pinched?
Have any pest chemicals been used? If so what and when?
Are plant's infected with pest's?


HYDROPONICS/Aero Ponics/Coco/Soiless/

How long has this problem been going on?
Are you growing in a PVC grow tent? (example: Hydrohut or any other non brand tents)
What system are you running? (DWC? Ebb flow? Aero? Water Farm? Flood Tables? and so on...)
What STRAIN are you growing?
What was the establishing technique? (Were the seed or clone?)
What is the age of your plants?
How long have they been in there mixture they are in now?(coco,soiless etc..)
How tall are the plants?
What PHASE are the plants in? (seedling, vegetative or flower) are the plants in?
What Technique are you using?
What substrate/medium are you using?(Hydroton, RockWool etc.)
What is the Water temperature?
What color are your roots? White? Brown? Are your roots slimy?
What Nutrient's are you using?(If growing soiless)
How much of each nutrient are you using with how much water? *Knowing the brand is very helpful*
How often are you feeding? (If using soiless)
How often are you giving nutrients? (If using soiless)
If flowering, when did you switch over to using Bloom nutrients?
What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd ect)
What is the TDS/EC/PPM you are using
What is the*pH*of the "Tank"?
How often are you testing your*pH/PPM/EC/TDS?
Are you sure your calibration is correct on your equipment?
When was your last watering?
What is your water temps?
When was your last feeding change? (ie. grow-bloom-micro-additional)
How often do you clean your system: example: Flush out water replace with clean water and nutrients?
What size bulb are you using?
How old is the bulbs you are using?
What is the distance to the canopy?
What is your RH Factor(Relative Humidity)?
What is the canopy temperature?
What is the Day/Night Temp? (Include flucutaion range)
What is the current Air Flow? (cfm etc.)
Tell us about your ventilation, intake exhaust and when its running and not running ?
Is the fan blowing directly at plants?
Is your water HARD or SOFT?
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water?
If using tap water, what is the ppm/EC/TDS of the water right out of the tap?
If using RO,Distilled,mineral water, what is the ppm/EC/TDS without any additives?
Are you using water from a water softener?
Has plant been recently pruned, cloned off of or pinched
Have any pest chemicals been used? If so, What and When?

Click to expand...