How to use indoor grow lights?

Hi fellow growers,

This will be my first indoor grow. I’ve purchased a 4x4 tent, fan/filter and 1500watt grow lights with veg and bloom settings. I’m wondering how exactly to cycle the lights? Should I have both on all the time, or is there a light cycle to adhere to? I am planning on growing White Widow, Critical Widow and Black widow for my first grow, from seeds. Also, should the seedling go in the tent right away?

Sorry for the ignorance, like I said, it’s my first indoor grow.

Thank you ahead of time for the help.


@2_minutes_in_the_box welcome to the forum. To be of any assistance I would also need to know the brand of the light.

Generally to start with a blurple light you should have the light hanging at 36 inches with just the veg on for germination and seedlings. As they start to grow and adjust to the light lower it a little every day until it’s about 24 inches away. Once they have adjusted to that you can flip the bloom switch on with the veg switch for the rest of veg and flower.

Lighting schedule for photos for veg should be about 18/6. 18 on 6 off. For flower 12/12. 12 on 12 off.

Hope this helps. Happy growing. :v::call_me_hand::metal:


Wow thank you so much! I had no Idea I need to lower it. I bought this light:

, by Bloomspect.


Follow manufactures hanging instructions. All leds are not created equally. It depends greatly upon what diodes are used etc.

Hang for correct ppfd/par in plant stages.

Looks like the sweet spot for flower ( non co2 enriched environment @ 750 ppfd) is going to be around 16"-18" for those lights.

200-400 PPFD: seedlings, clones, and mother plants.
400-600 PPFD: early to late stage vegging cycles.
600-900 PPFD: for the flowering, fruiting, or budding stage of plants.


@2_minutes_in_the_box That bloomspect one you’ll want a little lower. Based on the light info you’d want it at about 28 inches for seedlings and early veg. Lower it to between 20 and 24 inches for veg. Flower you’ll need to have it 18 to 20 inches. Remember on lights with UV and IR the intensity is more than what the PAR, PPF, and PPFD values say as manufacturers generally only measure the 400-700 nanometer range. Since yours has IR it’s actually putting out more photons than what it says. Happy growing. :v::call_me_hand::metal:


Thank you so much for your help.


@2_minutes_in_the_box you’re welcome. Happy growing. :v::call_me_hand::metal:

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