California Lightworks SolarXtreme 500 vs. Phlizon CREE COB LED 400w

The California Lightworks SolarXtreme 500 and the Phlizon CREE COB 400W LED grow light both rely on higher-quality COB (Chip-on-Board) LED diodes. These COB LED grow lights offer important advantages over traditional single-diode LEDs and are especially attractive for smaller indoor and hydroponic grow rooms. As regulators in multiple states tighten power limits for commercial cultivation, operating efficiency has become a critical factor when choosing LED grow lights.

Many growers have requested a direct comparison between these two COB LED fixtures. This head-to-head analysis is part of the ongoing GrowersHouse testing project, where we evaluate the real-world performance of the LED grow lights we carry. The comparison is appropriate: both models use COB technology and are produced by relatively new brands in the LED grow light industry.

Both LED grow lights incorporate direct AC drive technology, eliminating traditional LED drivers. This design choice reduces weight and fixture size while maintaining high PAR efficiency. Lower operating costs and strong photon output make both options appealing to serious indoor and hydroponic growers.

Quick Takeaways: SolarXtreme 500 vs Phlizon CREE COB 400W

• The California Lightworks SolarXtreme 500 is more expensive upfront but cheaper to operate over time. It uses only COB diodes, which improves coverage and likely extends fixture life. Its spectrum delivers higher deep red and infrared output, and it comes with a 3-year warranty. 

• The Phlizon CREE COB LED 400W combines fewer COB LEDs with older-style diodes, resulting in lower overall energy efficiency and less uniform coverage. However, its spectrum penetrates the canopy effectively and delivers relatively high levels of green, IR, and UV. The Phlizon has a 2-year warranty and is not currently sold by GrowersHouse.

Both fixtures achieve high PAR efficiencies: 2.25 µmol/J for the California Lightworks SolarXtreme 500 and 2.33 µmol/J (380–780 nm) for the Phlizon CREE COB LED 400W. The following sections break down how they differ in LED design, spectrum, PAR uniformity, and long-term operating cost so growers can decide which COB LED grow light best fits their room and production goals.

Why COB LED Grow Lights Stand Out

The SolarXtreme 500 uses only COB LEDs, while the Phlizon mixes COB modules with traditional diodes. COB (Chip-on-Board) LED technology in both fixtures provides several important technical advantages for indoor cultivation:

• Better diode stability at higher power levels.

• Broader PAR spectrum coverage from a single light-emitting source.

• Lower thermal resistance and improved heat management.

• Longer expected diode life.

For hydroponic growers and indoor cultivators, these characteristics translate into more reliable PPFD delivery, more stable spectrum over time, and fewer fixture replacements across multiple runs.

LED Grow Light Specifications Compared

The table below compares key LED specifications for the California Lightworks SolarXtreme 500 and the Phlizon CREE COB 400W. These metrics matter for canopy coverage, power planning, and long-term energy efficiency in both soil and hydroponic systems.

LED Specifications	California Lightworks SolarXtreme 500 LED	Phlizon CREE COB 400W LED
Wattage (Input Power)	400w	451w
Voltage Options	100-240v	100-265v
PAR Efficiency (µmol/J) [380–780 nm]	2.25	2.33
Total PPF Intensity (µmol/s) [380–780 nm]	900	1,050
PPFD Intensity (µmol/m²/s) [380–780 nm]	800 (@ 18") 500 (@ 24")	940 (@ 18")
LED Diodes	Proprietary CLW (8) COB (Chip-on-Board): Full Spectrum	(4) CREE COB (Chip-on-Board) | (68) (630–660 nm) | (10) (470 nm) | (6) cool white | (4) warm white | (4) (410 nm–UV) | (4) (740 nm–IR)
Amps	4 @ 100v | 3.3 @ 120v | 1.67 @ 240v	4.51 @ 100v | 3.76 @ 120v | 1.88 @ 240v
Mounting Height	18"–24" from canopy	18"–24" from canopy
Coverage Footprint Veg	Up to 5' x 5'	Up to 5' x 5'
Coverage Footprint Flower	Up to 4' x 4'	Up to 4' x 4'
Length	18" (45.7 cm)	21.25" (54 cm)
Width	8.5" (21.6 cm)	12.2" (31 cm)
Height	4" (10.2 cm)	3.15" (8 cm)
Weight	11 lbs	13.5 lbs
Warranty	3 years	2 years
Controllable	No	No
DLC Listed for Energy Rebates	Yes	No
IP Rating	N/A	N/A
UV and/or IR Spectra	IR only	Both UV and IR
Dimming	No	No
Cooling	Active (fan-based)	Active (fan-based)
Heat Output (BTUs)	1,280	N/A

Spectrum Differences Between SolarXtreme 500 and Phlizon CREE COB 400W

Because the SolarXtreme uses only COB diodes, it is expected to offer stronger stability over time and a longer service life. The Phlizon, by contrast, produces a more “complete” PAR spectrum by including several additional wavelengths, such as UV and IR, along with elevated levels of green and yellow light. The SolarXtreme COBs deliver significant deep red and IR output but no UV, while Phlizon adds UV radiation that can support increased resin production.

The SolarXtreme’s longer warranty (3 years vs. 2 years) reflects this emphasis on build quality. Another practical advantage is that the SolarXtreme 500 is listed for DLC energy rebates, which can offset installation costs in qualifying regions. The Phlizon LED is not DLC listed at this time.

Spectrum Graphs: What the Numbers Mean for Plants

The spectrums produced by the California Lightworks SolarXtreme 500 and the Phlizon CREE COB 400W from 380–780 nm are shown in the first spectrum graphic, alongside the absorption curves for chlorophyll and carotenoids:

California Lightworks SolarXtreme 500 vs. Phlizon CREE COB LED 400W

A second spectrum graphic adds curves from several established LED grow light brands—Growers Choice, Fluence, and HLG—for direct comparison:

CA Lightworks vs Phlizon vs Growers Choice vs Fluence vs HLG

Discussion (Graphic 1): A clear difference between the two LED spectrums emerges. The SolarXtreme produces slightly higher red (0.95 vs. 0.9) and significantly higher deep red (0.6 vs. 0.3), while the Phlizon produces more UV, blue (1.0 vs. 0.6), green, and yellow wavelengths.

In general, higher red (around 600 nm) and deep red (around 660 nm) levels are most valuable during flowering and reproduction, whereas higher blue (around 450 nm) is favored for compact vegetative growth. In this case, both LEDs supply usable quantities of red and blue, allowing growers to use either fixture across both veg and bloom cycles.

Overall, the Phlizon LED incorporates a broader PAR spectrum with relatively high intensities across all key wavelengths, plus UV and green light that can support resin production and yield. The SolarXtreme, however, stands out for its elevated deep red and IR output, driven by its COB-only array.

Discussion (Graphic 2): When the Phlizon spectrum is compared with Growers Choice, Fluence, and HLG LEDs, it aligns more closely with these established “full-spectrum” fixtures than the SolarXtreme does. Its elevated green and yellow components improve canopy penetration, helping maintain healthier lower growth and extend productive flowering deeper into the canopy. Strong blue and red intensities support balanced development through veg and bloom.

The SolarXtreme’s advantage is its high deep red output and strong IR component, both of which play critical roles in reproductive development and finishing quality. This elevated deep red and IR response appears to be linked to the wider spectral output that COB diodes can provide.

PAR Uniformity and Coverage

The PAR grid chart below shows PPFD distribution for the Phlizon CREE COB 400W LED over a 2' x 2' area. At this time, a comparable PAR chart is not yet available for the California Lightworks SolarXtreme 500.

Discussion: The main weakness of the Phlizon CREE COB 400W LED is its relatively low PAR uniformity. Across a 2' x 2' grow area, PPFD can drop by as much as 77.2%, whereas comparable high-end LED grow lights—such as the HLG 600 R-Spec—see PPFD reductions closer to one-third over similar coverage.

One way to improve uniformity is to use two Phlizon fixtures over a 4' x 4' grow area. This can even out PPFD across the canopy and reduce hot spots and dark corners. Because each Phlizon fixture is relatively inexpensive to buy, some growers may see this as a viable alternative to one higher-priced, more powerful LED.

However, the tradeoff is energy consumption. A single Phlizon can cost about $227 more per year in electricity than one SolarXtreme 500. Running two Phlizons over a 4' x 4' area could increase annual energy costs by around 225% relative to a single SolarXtreme—about $674 more per year.

Although a PAR chart for the SolarXtreme 500 is not yet available, its larger number of COB LEDs and design focus on coverage suggest that PAR uniformity is likely better than the Phlizon’s over a comparable area.

Cost and Operating Expense Comparison

Upfront fixture cost and monthly operating costs are critical for commercial and home growers planning multi-cycle production. The table below compares estimated fixture price and monthly energy costs for both LEDs.

Cost & Energy	California Lightworks SolarXtreme 500 LED	Phlizon CREE COB 400W LED
Estimated Fixture Cost	$470	$280
Adapter for Controller	N/A	N/A
Controller	No	No
Cost to run per month @ $0.13 per kWh (US avg.) (12–16 hr DLI)	$18.72 (12-hr DLI) – $24.96 (16-hr DLI) @ 400w	$30.42 (12-hr DLI) – $40.56 (16-hr DLI) @ 650w

Discussion: The Phlizon LED grow light is clearly more attractive from a pure purchase-cost standpoint, coming in at about 40% less than the SolarXtreme. For growers focused mainly on lowering upfront budget, the fixture offers strong value considering its spectrum quality and the low likelihood of needing additional UV or IR supplementation.

However, the reason for this large price gap is that the SolarXtreme 500 uses higher-quality components and has overall better build quality. This is reflected in its longer warranty and expected service life. The SolarXtreme is also likely to provide better PAR uniformity across a 4' x 4' grow area, thanks to its higher COB diode count and broader coverage from each COB module.

Practical Takeaways for Hydroponic and Indoor Growers

For growers running hydroponic systems, coco, or soilless mixes in compact grow tents and 4' x 4' rooms, both COB LED grow lights can deliver strong yields. The decision comes down to priorities:

• Choose the SolarXtreme 500 if you prioritize long-term reliability, lower monthly power bills, better PAR uniformity, and access to DLC rebates. Its stronger deep red and IR output can be particularly helpful in flowering-heavy rooms.

• Consider the Phlizon CREE COB 400W if upfront cost is the main constraint and you want a spectrum that closely mirrors other high-end full spectrum LEDs, including UV and enhanced green/yellow for canopy penetration. Just keep in mind the extra energy cost and less uniform PPFD distribution.

In short, the SolarXtreme 500 is designed as a long-term, energy-efficient workhorse with a robust COB-only array, while the Phlizon delivers a very complete spectrum at a lower purchase price but with compromises in efficiency and uniformity.

More LED Grow Light Tests & Comparisons

If you want to dive deeper into LED grow light performance before committing to a fixture, explore other recent GrowersHouse test reports and side-by-side comparisons. These independent measurements can help you align spectrum, PAR output, and energy use with your specific crop and hydroponic system.