Seedling light??

Discussion in 'Growing Marijuana Indoors' started by bongmaster4207, Oct 16, 2016.

  1. Hey guys I am going to start my grow in just a few weeks but I need some advice on the light I should be giving my seedlings. I will be growing auto flowers and I have 2 Mars300 LED lights but I've been told that they are too harsh for seedlings and will likely burn them. I need to know what type of light I should use until I introduce my LED's. Also, how many weeks until it's safe to put my Mars300 lights on my plants? I was thinking about a few CFL lights for the seedling/veg stage but I'm not really sure how long the "veg" stage is on autos... I've heard they start flowering awfully fast, after just a few weeks.

    Also, I need to buy a carbon filter and inline exhaust fan... The volume of air that I need to circulate is about 56 cubic feet (2x3.5x8 closet). I'd like to have something relativity quiet, but I really just want it to last a while. Any advice is much appreciated!!
  2. I started all my 3 Auto seedlings under a single Mars 300W., no burn problems at all.
    Just make sure they're at least 24" away from the seedlings...
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  3. These are almost week old, autos under a MarsHydro300 LED. The unit is about 2 feet from them. I have only experienced problems when I change to LED from something else, or have the LED unit too close


    Autos usually start flowering at around 3-5 weeks

    I could recommend an exhaust fan, what country are you in?
    • Like Like x 2
  4. Wow, that's great news! The less money I have to spend on lights the better lol. Have either of you done this before or is this your first time starting auto flower seedlings on a Mars300? Just wondering what kind of yield you got.

    I'm in the US and not in a legal state what so ever lol.
  5. CFLS will be right for the seedlings because it will not burn them. For some reason and in spite of the fact that the overall affect with the LEDs is cool, they burn hot to the actual plants. Start your seedlings under CFLS and keep and eye on them. The very first thing they do is build a root system. While this is happening, they don't grow much or use water so don't freak out and water, feed, or anything else. Once the root system is finished, you'll see new growth begin to put on at a decent pace. When this happens, your plants are ready for the LEDs. But you'll need to hang them high and lower them over a period of days down to the level where the plants get the most light...but it doesn't burn them. Best of luck. TWW
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  6. Thanks a lot TWW! How many watts should I be looking at if I get CFL's to start off the seedlings? I'm thinking I'm going to start 3 seeds at a time. Surely my little babies wont need too much wattage before I introduce the LED's. Am I correct assuming this?
  7. I have started seeds many times with this LED, I have two and have had them for a couple of years now. Each one usually gives me about 3oz. But auto yields can vary a lot if you're new to growing because any mistakes you make while they are vegging has a direct effect on the yield. As opposed to photoperiod plants where you can just veg a little longer to overcome any shortfalls.

    A good quality 4" exhaust fan should easily handle the heat from two of those LEDs. I have used two of them and a MarsHydro 144x3w and my 4" fan has just about handled it all

    This one should do it
    • Like Like x 1
  8. 20w over each plant is plenty for the first week or even two if growth isn't great. But your LED is perfectly fine, I have the same one and don't have any problems
  9. Yeah I think I'm just going to do what you're doing and start them on my Mars 300 and try not to burn them. Maybe later on I'll experiment with CFL's, but I have other equipment I need to buy still.

    Great! Do you use a speed controller with your fan? Also, will any 4" carbon filter work with this fan?

    Thanks a lot for the help! :)
  10. I do use a speed controller with mine, but it's always on full unless I have visitors, then I'll turn it down to the slowest speed to keep the noise down.

    I have this one, I think it cost £5. It's designed to dim lights, and is not grow related so it's much cheaper


    Any 4" carbon filter will fit the fan, but beware of cheap filters as these often don't work at all. Over here in the UK, Rhino Pro filters are the best, but in the US I believe Phresh filters are good ones. Hopefully another US resident could help you out on this. The UK and US don't share many brands. And whenever they do they seem to have different names strangely
  11. Awesome, that's a good idea! Do you know anything about the Active Air brand of inline fans? I trust you when you say the fan you recommended is a good fan, but I just really hate buying stuff from eBay :/ Any thoughts on this?
  12. I have never heard of that brand. What about Amazon, are you ok buying from them?
  13. Yeah for some reason I feel much more comfortable buying from Amazon. Do they have the fan that you have on Amazon? I've seen a few people use the Active Air brand fans. The only problem I have with the fan you recommended, besides the fact that it's on eBay, is that it is "unbranded". Well, that's what it says anyways lol.
  14. Oh right, we'll if you don't mind paying the extra yeah that would be better

    Check this out"+fan

    This fan is also a good one and a bit cheaper"+fan&dpPl=1&dpID=51JminCPW8L&ref=plSrch
  15. Hmm this is a pretty good deal. And it's sucking more CFM than the Active Air! Thanks! Could you explain to me a little on how the carbon filter works? Is the filter the large aluminum "can" the attaches to the fan or is the filter the sleeve that goes onto the metal "can"? I hope that makes sense... I've seen some that have the sleeve and some that don't. I will be using my filter to suck air through, not blow air through if that makes a difference. I posted the same question on another thread that I saw you were commenting on so don't worry about replying to both :) I need to order my fan/filter like today lol my lights just got in today!

    Edit: I was also thinking about getting a 6" fan and run it at like half speed or so so it's not always on full power.. Do you think this is a good idea or would that just be wasting money? I'd like for the fan to last a few years at least.
  16. essentially you want to pass the air through the activated carbon before it leaves your tent, you are correct in your pulling method it may take some tweaking to find a speed that doesn't impede the negative pressure and or smells
  17. I do not use a carbon filter, smell isn't a problem, yet! however most likely will build a homemade one if it comes disturbing to those I live with I would only really need one for them, unfortuenalty they don't like the smell I've come all too a custom too lol
  18. Man, this is awesome! I might have to try this... Thanks!:)

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