Anyone use Sf 4000 led light

Anyone use the sf 4000? Curious at what heights do you put it and what % dimmer , at all stages of growth?

@DrWoo does

Thank you @BobbyDigital I will see if they are available :blush:

I have an SF4000 in a 4x4. Lights up the space well. I have some issues with the corners, but that’s mostly because I blast the middle at lower height. I’m getting PPFD at around 1300 in the center where stems are high (roughly 16” from light) and 500 in the corners where stems are lower (roughly 20”-24”)


@TT - I just saw your other post. You need to measure your light to get proper height and dimmer. Get the Photone app for your phone and buy the LED or sunlight option (roughly $6). Use the dimmer to control temp (upward) and the height to control light intensity. Beginning of flower you should be around 700 PPFD, and ramp up to 1000 or so over the next few weeks.

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Thank you @DrWoo math is my worst, I will try to figure it out tomorrow, thank you

Groovy. PPFD is the amount of light delivered to the spot you’re measuring. It’s in the app. 300 early veg, 550 late veg, 700 early flower, 1000 mid and late flower. Ping me if you need me.


Do organic soils show this low of ppm’s this late in veg

I don’t understand what’s going on here. I’ve heard of slurry test but I’ve never felt the need to do one.

How to Test Soil Using the Slurry Method

  1. Gather some soil from the test area.
  2. Take the homogeneous sample and add equal parts of soil and distilled or deionized (DI) water in a 1:1 ratio. So, for 25 grams of soil you would add 25 mL of water.
  3. Stir the sample for 5 seconds.
  4. Let it sit for 15 minutes.
  5. Start stirring the sample again after 15 minutes, and take your measurement.

Wooopppps sorry this all was meant to go on my journal lol :grimacing:

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@TT i have responded to myself several times!

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Opps wrong thread but thank you, uggg added to much water

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