The fact is, no one makes a great 5x5 fixture based on the PAR maps I've seen. The fixtures are all designed to fix in a 4x4 space, so the edges and corners tend to be a lot weaker than the center in a 5x5 space. I'm wrestling with the same issues myself since I'm going to be setting up a 10x10 as well.
To overcome the weakness along the edges, I'm looking a this fixture from Mammoth to fill in the gaps
Introducing the Mammoth Lighting 100W Single Bar LED Grow Light - Your Ultimate Indoor Plant Growth Companion! Are you looking for a versatile, high-performance LED grow light that takes your indoor gardening to the next level? Look no further! Mammoth Lighting has designed this cutting-edge LED...
mammothlighting.com
As for the primary fixtures, here are the candidates
This 10 bar fixture from Mammoth might be OK without any additional fillers. There are a ton of these on the market, including on Alibaba, but the fact the Mammoth is stateside, offers a 5 year warranty, and has good customer service ratings makes it the preferred choice.
10 Bar Led Grow Light - ETL Listed - Mammoth Lighting has been developed by indoor growers over many years of careful experimentation and testing. Scientifically engineered to deliver the highest level of PAR output and balanced Coverage in the LED grow market. The Mammoth LED grow lights are...
mammothlighting.com
There's been some interest in the Geek Best Pro 630w which was only available on Alibaba. That's no longer the case. Some enterprising folks have opened a US business stocking them here. i love the even canopy for a 4x4, and with 4 of the single bar Mammoth units it looks quite promising.
LightGeek USA - Industry Leading LED Grow Lights
lightgeekus.com
Finally, I'm looking at the Photontek 600w ... I'd love to wait for the 1000w unit but that's going to depend on the veg cycle one I get set up again. The 600s will still need the 4 single bars to even out the lighting, but the quality and the spectrum are first rate.
X 600W Pro LED is a perfect solution for home-grow, grow tents, grow rooms and all kinds of indoor greenhouses | 600w led grow lights
photontek-lighting.com
Don't know if sharing my indecision with you helps or hurts, but those are my candidates for a 10x10. The costs are still around $4K-$4.5K for any of them.
After everyone gets finished telling you I'm an idiot and xyz lights are the way to go, we can move on to climate control and ventilation
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