Light leak through ac vent

Discussion in 'Growing Marijuana Indoors' started by slimjimham, Aug 6, 2011.

  1. So my lights are on at 10am off at 10 pm, there is a light leak only through the vent where it blows, should I do something about it or is the few hour light leak insignificant since it's very mild?

  2. That's how you produce a hermie or a screwed-up plant. There really is no such thing as a "little" light leak -- either you have total darkness or you have a light leak.

    Build a light trap on your vent.
  3. you don't need "complete" darkness...outdoor plants get lots of light on nights with full moons and dont hermie or get screwed up

  4. Agreed. As long as your not getting day light leaking in you should be fine.
  5. ^Ignorance.

    A full moon does not give off "lots of light." This has been discussed and analyzed ad nauseum here.
  6. For the record I wasn't agreeing on the full moon statement, but the fact on a night time light leak not being a problem.
  7. Fine. Still wrong though.

    It is possible to have an amount of light that is so low that it won't affect the plant. But you certainly cannot make a blanket statement that a night time light leak is not problem.

    How much light can a plant take without turning hermie? There is no one answer, it depends on the strain and individual phenotype, the nature of that light, many variables. And, none of us has an expensive light meter to truly, accurately measure light anyway.

    Let's put it another way: there is no reason to tempt fate. If you allow light into your grow during the dark period one of two things will happen: your plant will turn out OK or it won't. Why risk it at all? Total darkness eliminates any potential problem from light leaks. Building a light trap is easy. Telling someone that a tiny bit of light could be OK simply encourages them to think that if a tiny bit is OK, then a tiny bit more than that is OK, in which case even a little more than that should be OK, and before you know it you've got hermies.

    Humans perceive light, we don't experience it directly the way plants do. The full moon might look "bright" to our eyes, but that is because of the contrast we perceive between the lit moon and the pitch-black sky around it. By the same token, light leaking into our grow space might look like "a little bit" but actually could be more than we perceive it to be.

    But again, it's a pointless exercise, just play it safe and let in zero light, then there is nothing to worry about. You spend a bunch of money and effort on seeds, grow space, lights, fans, pH meters, soil, etc etc and then you jeopardize all that by taking a chance on doing something that is a known risk? Makes no sense. Button up, do it right, sleep well at night, and enjoy a bountiful harvest.
    • Like Like x 1
  8. I think that if the only light leaking in is from the moons ambient reflective glow then it should be fine. However, if one lives in a city and there is a decent amount of light pollution from street lights/cars then in that case it would most likely be a problem. I agree about being better safe then sorry. Don't let any light in.
    Peace friend!
  9. Well like I said my lights turn on at 10am so and light before then is the leak
  10. Is that ok?
  11. I say cover it up with a light trap or something. Your probably getting some daylight leaking in since they turn on at ten.
  12. What's a light trap? I was thinking of building a wood box with an opening on the bottom to put over the vent, painting it flat black and have it dump the cold air down (or up...)

    Any easier or better ways to do it?

    Thanks guys!!!
  13. take this advice he 100% right bro
  14. Hey i got a similar of problem I have a grow tent but if you have a light on outside and seal your self in it you can see around a few little tiny and I mean tiny specs of light through some of the stitching. I'm guessing this won't be a problem since
    1. I'm growing in my attic room where the lights will be off outside of the tent and the ambient glow of the tv at the other end of the room won't give off enough light to penetrate the stitch work on my tent IMO any way.

    2.even if all the above is completely incorrect I have a thick blanket that I can lay over it adding another layer of protection.

    Is any of this right will it work or am I gonna have to bite the bullet and buy a new tent for flowering in?

    But on thinking again are any grow tents completely (and i do mean completely light proof) like can you imagine having to be the guy stitching this damn thing together and having to check each damn stitch to make sure not a single spec of light would penetrate that fucker! Lol idk I'm no expert just wondering. Any one know any thing about this at all?
  15. We aren't there to see what kind of light you are talking about, but probably no, as I've said already.

    Let me google that for you :rolleyes:

    You're on the right track, you want to cause the air to go through at least 2 turns of at least 90 degrees and paint the inside of those turns flat black, then the air can move through but the light can't.
  16. So this would be perfect but how would I build this...

  17. #17 toastybiz, Aug 7, 2011
    Last edited by a moderator: Aug 7, 2011
    It doesn't need to be anywhere near that complicated.

    If you have round openings you can use two pvc pipe elbows. Or you can just build a box with cardboard. Paint the insides flat black.

Share This Page