Help im blowin it

First grow inside 2nd time. Lost 4 lady’s 2 auto 2 photo. Looks like I’m gonna blow it on the second round also. I have a vs 1000 full spectrum led "daylight " I think it 100watts. My seedlings are in a 2x2area in a 4x4 tent. Can anyone tell me what the height my light should be if I have it at 50watts?? Help

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Welcome to the forum! Start with the light 24- 30” above the plants and lower if you see the seedlings stretch.


What are the leaves and the stem doing if they point up and stem gets overly long they want more light, if they turn downwards and slightly twist then they’re getting to much .I start my Mars hydro at 50% 16 inches and my better hlgs at 32 inches 40% for single or 10% for double( their potentiometer is weird)

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I know, off topic. But how is their potentiometer weird? It’s just a line of resistance, so of course when you divert the power of two lights through one potentiometer it’s gonna change your scale. When you daisy chain potentiometers (correctly) you are actually disabling each one down the line.

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I’m not daisy chaining them they re weird because 0 % doesn’t = 0 light so I have to guess what the base wattage at 0% of the knob is

0% isn’t 0 tho. The numbers on potentiometers are just base guestimates. They are extremely simple technology. You move the wiper along the path of resistance. It never actually comes off of the path of resistance.


Of course. The range of resistance in use has to be in line with the voltage range you want. Like I litterally use a cord with potentiometer I had laying around for a fan up to 50w. It’s now on a fan that doesn’t go past 18. Adjusting the potentiometer does absolutely nothing. Since it gets the most wattage it can use even on the lowest turn.

Do these go to 11?


Using pot to control fan speed is different than how most of these drivers use them to control light output. Pot works same way as you describe, but actually sends signal to module within driver that is automated identified as type and then processed into control. In most cases that you will see on this forum is actually done by ramping output current of the driver. When resistance dimmer is used is actually controlled by impedance of dimming circuit. But same wires can provide same function using 0-10v or pwm, which wouldn’t work for what you’re doing with fan.

In some cases, the drivers are just not capable of dimming to off. So regardless of control, will never go to zero=off. They are pretty good at % of control being equal to % of output current. But that is not equal to % of light output. Have to remember that leds are resistive load, and that they will be more efficient as current and junction/case temps drop. If you’re controlling one aspect everything else isn’t necessarily linear.


The stems are purple the fan leaves were pointing up. I’ve done so much with the intensity and distance its very frustrating. Currently at 50watts at about 27". I picked that setting 5 hrs ago. Maybe it will work??