SpiderFarmer SF2000Pro Grower - Optimum Setting

[2ShedsJackson]

I've got 2 plants currently growing under an SF2000Pro light but wondering what dimmer setting I should be using. They're both in week 4 of flowering.The manufacturers info is saying that for flowering I should be set at 100% @ 12-18" but up until now I've been dimming down to 70% but still getting yellow leaf tips as the photos show.
Does it look like light burn or something else. I'll ramp it up if it's gonna give bigger buds but don't want to cause damage. Anyone else using these lights at full power?

[DabberDog]

Give her all she's got, Scotty! That fine-looking dope you got going on is in late-stage flowering and probably why you're getting yellow.
I'm not saying you will get these colors. Only that this is what you have going on. The Cannabis Autumn Color Effect (Get Colorful Leaves!) | Grow Weed Easy
What are your nutrients?

[2ShedsJackson]

Nutrients are Bio Bizz. Grow, Bloom & Topmax.

[DabberDog]

I'm also in a coco 3x3 but I grow four at a time. Was. Takes too much defoliation to keep four in that space. I'm about to drop down to two, twice or thrice topped, or manifolded. I'm hoping the less defoliation will give me plants more like yours.

[2ShedsJackson]

If I had my time again, I'd have gone with a 2 x 4 for easier access. Kills my back reaching in to get mine out from the back of the 3 x 3.
The plant on the right was topped once, the one on the left sprouted two main stems from seed so I left it alone. Both have been LST'd.

[Bluey]

I have 2 of those. Use them at 100% in flower. I only use them for photoperiods in veg or for autos. They are not powerful enough to light a 4x2 properly in flower

[kingfish]

I also use the SF2000 for vegging. When it's time to flip them, they go into the tent where I have an SF4000 for flowering. My tent is a 4x4x7.

[Allenpro]

I have one of those I bought for a 2 X 4 tent with less than satisfactory results now I use in a 2 X 2 ft tent I use for seedlings, breeding and rooting clones. Unfortunately the truth in advertising requitement never made it to the LED industry and you can see they are exaggerating about the coverage from the PPFD map.

[Allenpro]

2 of those lights would cover your 2 x 4 tent with some to spare probably.
The one I have convinced me that bar type lights give the best coverage

[DabberDog]

I'm with you about the back.
My tent is on a dolly. When I have to reach into the back, I can roll my tent out and unzip a side.
The one with two main stems. Do you mean you sprouted two plants from the beginning or one developed two mains? The former is twins. The latter is called a codominant stem.

[2ShedsJackson]

It developed two main stems, like an egg with two yolks.