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Light leaks

Hello Growmies. I’m in need of some help. I have light leaks around the zippers of my grow tents, and around the seams what can I use from the inside to cover those leaks. Thank you.

Foil tape from lowes home depot. Get a bright light going outside tent. get inside tent with tape and a small light. And start taping. Turning the small light off to see the leaks and on so you can tape use very little tape.

On zippers its trickier. Have to follow the curve and take strips and fold in half and attach making them longer like an extension of the inner zipper flap takes time PIA. But every tent has holes because the needle from the machine sewing the tents.

I throw a large sheet and or beach towel over the tent when it’s lights out time. I cover the front side with the zippers. There’s still some light in the grow room at times and I’m paranoid about it. Just don’t block your air intake/exhaust.

I never flower indoors so I just don’t care…lol…makes my life simple…

this is another reason i select power supplies with green lights. If at all posibble.

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I have a bitch of a time getting any kind of tape to stick to the tents for more than an hour. Duct tape, gaff tape, nothing sticks for long. How do people light-proof the rectangular, mesh air intake windows at the bottom of the tent when you can’t keep the room pitch black all the time? I tried a piece of cardboard with ducting affixed, but like I said, none of the duct tapes hold anything to the tent material.

I added a vent to my grow room to help with the heat and created a light leak. I now have seedy buds probably because of that leak. I didn’t take the light leak seriously … another beginner mistake.

I have a constant light leak in the bottom of my tent where my recirculating tubes exit to my reservoir. I can see quite a bit of light leaking out from the bottom when my lights are on. I tried using black duct tape, but it doesn’t stick very well. Anyways I’m 5 for 6 on my grows being completely seedless. I had some seeds on my 1st run growing GDP. I’ve always gotten nice dense buds too. I also have 2 power supplies at the top of the tent that give off an orange light. I wrapped most of it in black duct tape, but it still glows.
But my rooms are blacked out, and the only light that could leak in is from the rooms light bulb. All that leaked in light during lights out has never effected my grows.
That could mainly be because I always have had strong stable genetics, and not weak genetics that can self pollinate after some minor stress. That’s just my opinion. :v:

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usually a tent has a flap that covers the vent hole. the flap and tent have velcro on them which sticks just fine been using the 2 4x4 vivosun tents for over a year with no issues. i also keep my flower tent in the second room of my basement and my veg tent in my first room but light still does get into the second room but never had any issues. on my flower tent there are 2 vents one on each side the one side that faces the wall i leave open for intake but the other one i close with the velcro flap just incase. also this might sound unmanly lol but learn to sew fr if ur tent doesnt have the velcro flap make one and sew the velcro on the tent and flap and there u go, personally i did not like the exhaust of the tents so i bought a 6 inch duct starting collar measured out the center traced the duct collar drilled holes in the duct collar, then stuck it on the hole i traced, used a sewing needle and thread stitched the collar to the tent, then cut the traced hole and bam the best exhaust you could ask for, i also did a DIY true inline filter that is end to end in and out used flex duct from the collar to the filter, added the exhaust fan to the filter then used more flex duct, cut a hole in my homes hvac return duct, added another starting collar and attached the flex duct from the fan/filter. by doing this my hvac unit is sucking in the exhausted air dehumidifying it and going back into my home, with the carbon filter removing the smell i am not wasting air exhausting it outside which saves money. i also tapped into a output from my hvac and if it ever gets to hot or cold i have flex duct that i can add into the room, and in the winter because of this and my furnace being in the same room the flowers are getting ALOT and i mean ALOT of FREE CO2 and my buds are huge. BTW I KNOW NOTHING ABOUT HVAC EXCEPT FROM WHAT I GOT FROM YOUTUBE AND ONLINE BUT THE BIGGEST HELP WAS MY BUDDY HERE WHO HELPED ME FINALIZE THE DESIGN AND CONCEPT SO I MUCT THAT MY GROWMIE @hoppiefrog

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Just use the silver metal sealing ducting tape. That’s what i use for light leaks and it sticks to everything. Very well.

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Ima flippin vampire. The house is always dark anyways!!! Lol

3 layers on windows

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Hey brother always happy to help solve a problem :facepunch:, where there’s a will there’s many solutions;)

For your air in leaks have u see. A light baffle box ? Or u can just use 8" flex and make a coil spray inside w flat black to eat any escaping light :wink: if u need more info I can send u a drawing and some pics to help u understand, I use one to keep weather out of my air In, At winter time

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Ok i have been pondering this in my head… what are you thought … to anyone… if doing outdoor grows plants get sun then moon and stars the plant is never in total darkness so aren’t the moon and stars light leaks? Or are they different somehow? Maybe considered “green light”? Why doesn’t this effect the plants? Or does it? Thank you all!! I enjoy reading your replies kk


I seem to always have seeds outside.

moonlight is not enough lumens to disturb the light cycle. Any more than moonlight your in trouble.

Thank You @preybird1

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If we wanna cut and paste here:
What Constitutes Daylight?

Cannabis needs an uninterrupted night period of a certain length to begin and continue flowering, usually 10 or more hours. What isn’t clear is at what point does the plant respond with light-reactive hormones that indicates when the night has begun and ended. For example, the sky lightens gradually for some time before sunrise and darkens gradually after sunset. Additionally, the full moon reflects quite a bit of light onto the earth at night. That the light needs to be of a certain intensity and duration to be able to alter the hormonal balance related to flowering in Cannabis is clear, but the exact value of that intensity and duration remains a mystery. This would be a great research topic which would benefit Cannabis cultivators of all varieties.


Plants grow best in perfect darkness,they Hermie less and ripen faster.mother nature is great but plants can be pushed harder when we understand what a plant prefers and see what the limits are.