There is no such thing ever in the history of growing weed as to much light, never. I like my lights to hang 20" to 24" above canopy. I also want my tents tall so that’s why I use standard gorilla tents with high cfm kit and exhaust fan external of tent. This gives me a 7’ 11" tent to work with. My ceiling height misses by 1" being able to use a 2’ extension kit on my tents. One 350R will not get me the ppfd I want unless I run the light at 15" or closer by there own independent ppfd report and confirmed by my MQ-610. And that is to close for me to run my lights. Two fixtures at 20" to 24" will give me my target 900 ppfd to 1000 ppfd with the ability to go into CO2 land down the road without issue if I decide to go there and crank them on up. I expect to be running each fixture between 200w to 240w. My dual HLG 260 Rspec V2’s are running very good at 230w per fixture in my 3x3 with a ppfd of 940 including UVA. Cranking them up all the way to there max of 257 watts each results in a PPFD of 1200 at 24". So don’t worry. It’s all a numbers game. One I would not play without years of experience and a Apogee meter. Enjoy your grows and I will enjoy mine… 
@Blastfact I love lighting to access myself but one would be plenty I also run two 300 l in a 3X3 with UV and a scorpion Diablo in the 4x4 with two UV
One will not get the numbers and the even spread I want the way I want them. I have all ready tested with one fixture. My other option would have been one 320W XL QB648 LED Kit. But in the end one fixture would not have got me the max capability I want nor the spread. One fixture maybe enough for you and others, cool beans. I want the power and even spread.
So light burn and light bleaching is all in our minds? LOL!
No…these things exist!
“There is only so much light your marijuana plant can take.” - First sentence from the Grow Guide on light above.
HLG also clearly states on their site the PPFD and overall intensity is increased in a tent or enclosed space. They don’t test lights in a tent they’re tested in a lab, a big wide open darkened room with zero reflections.
Pound and a half SoG run under a single HLG 350R at 80% approx 24" above the canopy.
Works just fine for me!
And why would anyone waste CO2 in a tent? You can never achieve the potential increases that CO2 will benefit from in a tent space! LOL!
I’m not a believer in any religion or political party that tells people what to do, so knock yourself out, but I KNOW it’s not needed to grow great weed in that space from experience, not belief!
Happy Growing Everyone!!!
Do you feel better???
No better than you feel superior, I guess…
WTF is wrong with you??? First you can’t do basic math and understand how two fixtures can fit in a 2x4. Now you have escalated to this level of BS and ego and turn on me then claim I feel superior. I have never said anything to claim superiority. I have never said that duals are needed as a general rule of thumb or otherwise. You need to back your bus up. Enjoy your day!
350Rs in dually mode with UVA. Idling away at 400 PPFD and going to 600 PPFD in a couple of days at 3.5 weeks old and starting on half strength nectar of the gods sampler pack ferts. Running cooler than the 100 V2 at 360 PPFD.
Nice! Going to be sweet grow!
How did you bolt them together?
