Autoflowers in wk 5 - distance of LED to grow

Growing 3 autoflowers (20/4) using Phlizon 1200w LED. Am VERY concerned based on other comments in this blog that might light distance is WAY to close. Is the Phlizon too powerful? Using both veg and flower switches set to “ON”. Currently set at about 12" - 14" from tops of grow.

I can easily move lights to 48".



The Phizon 1200w is actually only a 250 watt light. These types of lights also produce a lot of heat, so too close could be defined as a positioning that heats up your canopy too much. The light is definitely not too much for 3 plants, and you will struggle to flower all 3 with the one light.

Lights that are too close will produce compact, dense plants. Compact and dense is not what you want to maximize yield. I would place the light far enough away that the heat from it does not impact canopy temps, but not so far away as to cause excessive stretching between nodes.

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Thank you!!!

You may have partially answered a different issue. I have a different grow going using the same brand of LED (a separate Phlizon1200). We have one auto flower in week 9 which we call the “alien” - her buds are VERY far apart and she is the tallest we have grown (about 20") of this strain. I guess fro some reason she was stretching for the light. Thanks again!


It’s best to just Google your light manufacturer and see what there recommendation is. Each light is close to a light of it’s own general make up. As in 1 LED to another, to the point that each has the same amount of diodes. The difference is the make and manufacturer of said diodes.
Some has more intently than others.

I have a question about fans and carbon filter. Here’s what I have at home for indoor growing. 200 CFM 4-in blower fan, a 440 CFM 6 in exhaust fan. And then I have a 4-in carbon filter. Can I use this setup if I take a 6-in fan and put a reducer on it to fit my 4-in carbon filter. I know between the filter and hoses it can reduce the airflow by 30% on the exhaust fan. Or do I have to buy a 6-in carbon filter. I’m trying to get by with the setup I’ve got but I just need to know if I’m able to use this setup.


A good question!

Calculate the cubic footage of your grow area. Mine is about 800 cu ft. Your 200 cu/ft “scrubber” will process my entire grow room every 4 minutes. If it slowed down 30% due to other issues, you will still be fine. My concern running a similar sized scrubber in my grow room is heat build up. If I run my scrubber too much the temperature the grow room starts to rise. What I do if the temp starts to rise is I use a rheostat on my scrubber to turn down the rpms a little.

i have this large skrew in flouro it 55w 3885lm 6550k and its just the room light but i notisted groth when its on as well as my 4 x full spectrum leds 300w