raise light and power to get hight temps and better venting

pvmhobostarted grow question 1y ago

so whats would be best option for me i have my light on 240w (25%) around 3 ft from plants my tent doesn't get over 74 and its not venting as much as id like my ppfd is around the 300 mark should i raise light and turn to 400w (50%)

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Setup. Lighting

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All_our_small_plantsanswered grow question 1y ago

Hi, so here are a few key points because the optimal PPFD varies depending on the growth stage of cannabis: Germination: 100–300 µmol/m²/s Vegetative Phase: 400–600 µmol/m²/s Flowering Phase: 600–900 µmol/m²/s But more important is the DLI value, as the DLI indicates the total amount of photosynthetically active light that a plant receives within 24 hours, measured in mol/m²/day. It combines light intensity (PPFD) with the duration of illumination. For cannabis, the ideal DLI value is between 20 for seedlings and in the first weeks and 40-45 mol/m²/day during flowering. You can gradually increase in between. If you use the app Photone, you can measure the PPFD and the DLI value there. You need to specify the hours your lamp is on and what light spectrum it has. This way, you can position your lamp ideally. The further away it is from the plants, the more area it will cover, but it will require more intensity.

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Ninjabudsanswered grow question 1y ago

I’d probably move the light up it probably will help them strech out some

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Ultravioletanswered grow question 1y ago

Higher light with stronger intensity will give you a better spread across the space. At 2-3ft you will have a strong central pffd and weaker sides. If electrical concerns are priority then keep it low and dim. If a more evenly distributed ppfd is your goal for growing 7 plants then raise it as high as it goes and blast it. This will give you a far more even 300ppfd across the canopy. Although your light looks like it fits tent very well. More output = more heat too. Ambient temp should be measured from canopy and you don't want to go over 77f anyway unless your supplementing co2 or transpiration is running hard. You won't get much venting until the plants get bigger, once they start moving more water. You can vent 24/7 if you switch fan on or have it set to unattatainable , got to understand what it is your venting for and why first.

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TruTraTrianswered grow question 1y ago

You can roughly balance watt and height – higher watt at more distance can give similar PPFD to lower watt closer in. Example: 50% power at 24" might equal 25% at 12", depending on the light’s optics. And: by adjusting both, you also influence tent temperature – higher power = more heat, more distance = cooler canopy. Easiest way is to measure PPFD, but experimenting and observing is a great way to learn too. Everyone throws photone app around.. probably got to test it too 😆

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Ninjabudsanswered grow question 1y ago

If your trying to raise the temps yeah I’m sure upping the light intensity will definitely increase the temperature Also I suggest if you want better circulation in the tent to get a fan that attaches to a tent pole and a fan that gos back and fourth helps all the air in the tent get moved around

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