Under-Canopy Lighting Compared: Gavita vs Faven R8 vs Chroma
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Under-Canopy Lighting Compared: Gavita vs Faven R8 vs Chroma
A commercial grower came to us frustrated by the bottom third of his plants. The colas up top were dense and frosty, but the lower canopy was all larf, the airy popcorn that trims slowly and grades poorly, and he was tired of clearing it. He had heard under-canopy lighting could fix it and wanted to know which to buy: Gavita's under-canopy fixture, or one of Faven's, the R8 or the Chroma. It is a great question, and the honest starting point is that all three solve the same real problem well. The harder, more useful question is which one fits your room, your top light, and how much control you want, and that is what this guide is about. We sell under-canopy lighting and have no reason to push one brand over another, so what follows is a straight comparison. We don't upsell.
If you are newer to the idea, we will start with what under-canopy lighting actually is and whether you need it, then compare the three fixtures in detail. For the bigger lighting picture, this pairs with our main grow light buying guide.
The 30-Second Answer
- All three light the lower canopy your top fixtures cannot reach, reducing larf and lifting lower-bud density, color, and total yield. The gains come from the technique itself; any of these done right pays off.
- Gavita Under Canopy 150W: full-spectrum, dual-sided (designed to run between rows), 450 umol/s at 3.0 umol/J, dimmable, controller-ready. The full-spectrum, between-row choice.
- Faven R8: a 120W single-sided bar with a fixed 80%-red spectrum and simple 0-10V dimming. The plug-and-grow choice that complements a full-spectrum top light.
- Faven Chroma: 120W plus an independent far-red channel and a tunable R4-R9 spectrum, run through a controller. The choice for growers who want to dial spectrum across the flower cycle.
Pick on spectrum philosophy (full versus fixed-red versus tunable), physical layout (dual versus single-sided), and how much control you want. We carry these and will match the fixture to your room, not your budget ceiling. We don't upsell.
What is under-canopy lighting, and do you need it?
Under-canopy lighting, also called interlighting or supplemental canopy lighting, places light fixtures low, inside or beneath the plant canopy, to reach the lower and mid sections that overhead lights cannot. The physics behind it are simple: a strong top light delivers excellent intensity to the top foot or so of a dense plant, but light falls off quickly through layers of leaves, so the lower canopy can sit at a small fraction of the intensity the tops enjoy. That light-starved lower zone is exactly where larf and popcorn buds come from. Under-canopy fixtures add targeted light down there, raising total plant photosynthesis and improving the density and quality of the lower flower. The benefit matters because cannabis is unusually responsive to light: a controlled indoor study found flower yield increasing nearly linearly with light intensity across a wide range, so giving a previously dim zone usable light is a logical way to convert wasted lower growth into harvestable flower.
That said, it is not for everyone. Under-canopy lighting earns its keep most in tall, dense plants, in sea-of-green or trellised setups, and in commercial rooms where squeezing more graded flower out of the same footprint pays for the hardware. Short plants, sparse canopies, and small home grows with good light penetration often see little benefit, and the labor and cost may not be worth it. Manufacturers commonly advertise yield gains in the range of 20 to 30 percent and a return on investment within a single run, and many growers do report strong results, but treat those as vendor figures rather than guarantees; your outcome depends on your canopy, genetics, and how well your top light already penetrates. If your lower buds are already solid, you may not need this at all, and we will tell you so.
Meet the three fixtures
All three are purpose-built commercial under-canopy fixtures, IP66-rated for wet rooms and backed by five-year warranties, but they take different approaches. The Gavita Under Canopy 150W is a 150-watt, dual-sided bar that emits light from both faces, which is why it is designed to slip between rows and light two sides at once. It puts out 450 micromoles per second at an efficiency of 3.0 micromoles per joule, runs a broad full spectrum with enhanced blue, spreads light across a wide 155-degree angle, dims down to 10 percent, and integrates with commercial controllers such as Trolmaster. It carries the backing of Gavita, a major commercial lighting brand with deep distribution and support.
The Faven R8 is a 120-watt, single-sided 46-inch bar from Faven, a company that builds under-canopy lighting and little else. It runs a fixed spectrum that is roughly 80 percent red, deliberately red-heavy so it complements the full-spectrum light from your overhead fixtures rather than duplicating it, and a bubbled lens spreads that light evenly. At 2.9 micromoles per joule, it uses simple 0-10V dimming with no software or learning curve, which is why it is Faven's best-seller and the easy plug-and-grow option. The Faven Chroma is the flagship: also 120 watts, but with an independent 15-watt far-red channel and a fully tunable spectrum ranging from roughly 40 to 90 percent red (Faven's R4 through R9 range). It runs through a controller, either Faven's simple CX2 or the wireless, app-based GrowFlux, letting growers program spectrum and far-red by flowering stage, balanced for bulking and warmer and redder for ripening.
Spectrum philosophy: full, fixed-red, or tunable
The single biggest difference between these three is how they think about spectrum, and it shapes which one fits your room. The Gavita runs a full spectrum, a complete light with white and enhanced blue, so it behaves like a smaller version of a top light placed down low and supports overall growth on its own terms. Faven takes the opposite, and arguably more purpose-built, view: the R8 runs a fixed, red-heavy spectrum specifically because the lower canopy under a full-spectrum top light is mostly missing red, so a roughly 80 percent red bar fills exactly that gap and pushes ripening and color from the bottom up. The Chroma splits the difference and then some, letting you tune from balanced to deep red and add an independent far-red channel, so you can run a fuller spectrum during bulking and shift redder for ripening. None is simply better; the right answer depends on what your top light already provides. If you want an under-canopy light that stands on its own, the Gavita's full spectrum appeals; if you want to surgically complement an existing full-spectrum top light, Faven's red-forward approach is the more targeted philosophy.
Dual-sided versus single-sided design
Physical design decides where each fixture wants to live. The Gavita is dual-sided, emitting light from both faces, which makes it ideal for running down the aisle between two rows of plants and lighting both at once, a natural fit for inter-row placement in trellised or bench-grown rooms. Faven's R8 and Chroma are single-sided bars meant to sit within or beneath the canopy and throw their light in one primary direction, with the R8's bubbled lens spreading it evenly. Neither approach is universally superior; it comes down to your layout. If your plants are arranged in rows with walkable gaps where a dual-sided bar can sit between them, the Gavita's design is efficient. If you are tucking bars into the canopy of a sea-of-green or a single dense bench, the single-sided Faven fixtures place more naturally. Picture exactly where the bars will physically go in your room before you choose, because that often settles the question faster than any spec.
Output, efficacy, and power draw
On raw numbers the three are close, with a slight edge to the Gavita. It draws 150 watts and delivers 450 micromoles per second at 3.0 micromoles per joule, while the Faven fixtures draw 120 watts at 2.9 micromoles per joule, with the Chroma adding 15 watts of far-red on top. The Gavita is therefore a bit more powerful and marginally more efficient per fixture, though the difference is small and both are strong, modern numbers. One important caveat for under-canopy work: more is not automatically better here. Under-canopy lighting is supplemental, and the lower canopy wants a moderate boost, not the blast of intensity a top light provides, so the practical goal is adding usable light to a dim zone rather than maximizing wattage. All three are right-sized for the job, which is precisely why you use purpose-built under-canopy bars rather than cramming another full-power top light underneath. Match the number of fixtures to your bench size using the manufacturer's layout guidance rather than chasing the highest wattage.
Can you just use a spare LED bar under the canopy?
It is a fair question, since growers often have an extra bar light lying around, but the answer is usually no, not well. Commercial top-light fixtures are built to run at several hundred watts and deliver intense light from a distance, which is far too much intensity to place directly inside a canopy; pointed at the lower bud sites from inches away, a full-power bar scorches rather than helps, and it dumps significant heat into the dense, still air where you least want it. Some growers do repurpose a dimmable top-light bar at its lowest output, around a third of full power, to approximate a supplemental level, and that can work in a pinch. But purpose-built under-canopy fixtures like these are engineered for exactly this job: lower wattage, a beam and form factor meant to sit among the plants, an IP66 rating for the humid lower canopy, and a spectrum chosen to supplement rather than duplicate your top light. That is why we steer growers toward a real under-canopy fixture instead of improvising with a top light running too hot.
Control and complexity
How much you want to fiddle is a real deciding factor. The Faven R8 is the simplest by design: plug it in, set intensity with a basic 0-10V dimmer, and you are done, with no software and nothing to learn, which is a genuine virtue in a busy commercial room. The Gavita sits in the middle, fully dimmable and built to integrate with commercial controllers like Trolmaster for scheduled, room-wide control, which suits operations already running a controller ecosystem. The Faven Chroma is the most capable and the most complex: through Faven's CX2 controller or the wireless, app-based GrowFlux system, you can program spectrum and far-red by flowering week, which is powerful for growers chasing specific quality outcomes but is more to set up and manage. Be honest with yourself about whether you will actually use spectrum scheduling. If you will, the Chroma rewards you; if you will not, you are paying for capability that will sit idle, and the simpler R8 or the full-spectrum Gavita is the better value.
Far-red and the spectrum-feature question
The Chroma's independent far-red channel is its headline extra, and it deserves an honest look. Far-red light, around 730 nanometers, is associated with faster flowering responses and some stretch, and many growers value the additional lever, particularly for ripening and quality. It is a legitimate tool. The caution is simply not to assume that every spectrum feature automatically translates into more yield or potency, because the evidence on spectrum add-ons is mixed and product-specific; a controlled study on ultraviolet light, for instance, found that adding it did not increase yield or cannabinoid content. Far-red is not UV, and we are not equating them, but the lesson carries: buy tunability and far-red because you want the control and intend to experiment with it, not because a spec sheet implies a guaranteed bump. For many growers, getting adequate, well-placed light into the lower canopy at all is the change that moves the needle, and spectrum fine-tuning is a refinement on top of that foundation.
Cost and return on investment
Pricing tracks complexity, and we will speak in relative terms since exact prices shift. The Faven R8 is the most accessible per fixture, a straightforward bar with simple dimming, which is part of why it sells so well. The Gavita sits at a premium befitting the brand and its dual-sided, full-spectrum build and controller integration. The Chroma is typically the most expensive of the three once you account for its tunable hardware and the controller it runs through. On the return side, manufacturers point to yield gains around 20 to 30 percent and payback within a single run, and under-canopy lighting can also qualify for utility energy rebates in some areas, which helps the math. We would temper that optimism with realism: the payback is real in the right room with a dense canopy that genuinely has a light-starved lower zone, and much weaker in a setup that does not. Run the numbers on your own expected extra graded flower against the hardware cost before committing a whole room, and start with a partial deployment to verify the lift if you are unsure.
Which should you choose?
Because all three deliver the core benefit, the decision comes down to fit. Choose the Gavita Under Canopy 150W if you want a full-spectrum, dual-sided fixture to run between rows, you value the Gavita brand and its controller integration, and you would rather have a complete light down low than a red-only complement. Choose the Faven R8 if you want the simplest, most affordable plug-and-grow option, you run a full-spectrum LED top light that the R8's red-heavy spectrum can complement, and you do not want to manage spectrum at all. It is the easy, proven default, and Faven's best-seller for good reason. Choose the Faven Chroma if you want to tune spectrum across the flower cycle and add far-red, you are chasing specific quality and color outcomes, and you will actually use a controller to run spectrum recipes. All three are IP66-rated and warrantied for five years, all three address the same larf problem, and the yield ultimately comes from the technique more than the badge, so buy the one that fits your room and your workflow. We stock under-canopy lighting and will match you to the right fixture, not the priciest one. We don't upsell.
Installation and practical tips
However you choose, a few practices get the most from under-canopy lighting. Place the bars within or just beneath the canopy where the lower bud sites are, not on the floor, and use stands or mounts rather than improvising, since stable, correct positioning drives the result. Aim for a moderate supplemental intensity at the lower canopy rather than blasting it, and use the dimmer to ease in. Mind the heat and airflow, because adding fixtures inside a dense canopy can create still, warm pockets that invite mold, so pair under-canopy lighting with good air movement, as covered in our ventilation guide, and keep an eye on humidity using a VPD chart. Take advantage of the IP66 rating by cleaning the bars between runs, since dust on a fixture buried in the canopy quietly costs you output. And because these fixtures live among the plants, route and secure cabling carefully for safety and easy maintenance. Good canopy management, such as the trellising covered in our SCROG guide, also helps by opening the structure so under-canopy light reaches more bud sites.
Under-canopy lighting versus lollipopping
The traditional answer to a light-starved lower canopy is lollipopping: stripping away the lower growth that will only ever make larf, so the plant concentrates its energy on the strong upper colas. It is cheap, effective, and still the right call in many grows. Under-canopy lighting offers the opposite strategy, keeping that lower growth and giving it enough light to develop into worthwhile flower rather than removing it. The two are not mutually exclusive; many commercial growers still do a light lollipop of the very bottom and lowest interior growth that even an under-canopy bar cannot save, then use under-canopy lighting to develop the mid and lower-mid canopy that is worth keeping. Think of it as a spectrum of choices: lollipopping alone is the no-cost option that accepts a smaller plant, under-canopy lighting is the investment that aims to make more of the plant productive, and a combination often works best. Good canopy management, such as trellising and selective defoliation, complements either path by opening the plant's structure so light reaches more bud sites.
Common mistakes with under-canopy lighting
A few avoidable errors blunt the results. The first is treating an under-canopy fixture as a primary light; it is a supplement to a proper top light, not a replacement, and the top light still does the heavy lifting. The second is running too much intensity down low, which stresses the lower canopy rather than helping it, when a moderate boost is the goal. The third is mismatching spectrum to your setup, for example adding a full-spectrum bar when your room really needed a red complement, or buying tunable spectrum you never adjust. The fourth is deploying under-canopy lighting in a grow that does not need it, a short or sparse canopy with good penetration, and then being disappointed by a thin payback. The fifth is ignoring the added heat and stagnant air inside the canopy, inviting mold in exactly the dense zone you are trying to improve. Avoid these, match the fixture to your room, and under-canopy lighting becomes one of the more reliable yield upgrades available to a dense-canopy grower.
What We'd Tell You at the Counter
If you asked us to choose between these three, we would first make sure under-canopy lighting is right for you at all, because in a short or sparse canopy it may not be worth the cost and labor, and we would say so. If your lower canopy genuinely sits in the dark, we would ask about your room layout and your top light. For rows with gaps to run a bar between, and a preference for a full-spectrum light that stands on its own, we would point you to the Gavita. For the simplest, most affordable way to complement a full-spectrum top light and lift lower-bud color, we would point you to the Faven R8. And for a grower who wants to program spectrum and far-red across the flower cycle and will actually use a controller, we would point you to the Chroma. We would remind you that the yield comes mostly from lighting that dark zone at all, that vendor yield claims are optimistic targets rather than promises, and that placement and airflow matter as much as the fixture. We sell these and make none of them, so we would rather match you to the right one than the most expensive one. We don't upsell.
Frequently asked questions
Does under-canopy lighting actually increase yield?
In the right grow, yes. By adding light to the lower canopy that overhead fixtures cannot reach, under-canopy lighting raises total plant photosynthesis and converts airy larf into denser, better-graded flower, which is consistent with research showing cannabis yield rising with light intensity. Manufacturers commonly cite gains around 20 to 30 percent, though those are vendor figures and real results vary with your canopy density, genetics, and how well your top light already penetrates. The benefit is largest in tall, dense, or trellised canopies and smallest in short or sparse ones.
Gavita Under Canopy or Faven, which is better?
Neither is universally better; they suit different rooms. The Gavita is a full-spectrum, dual-sided fixture designed to run between rows, with a slight edge in output and efficiency and integration with commercial controllers. Faven specializes in under-canopy lighting and takes a red-forward approach designed to complement a full-spectrum top light. Choose the Gavita for a complete light between rows, and a Faven fixture for a targeted complement, based on your layout and top light rather than an expected yield difference.
Faven R8 or Chroma, which should I get?
The R8 is the simple, affordable, fixed-spectrum bar with 0-10V dimming and no learning curve, ideal if you want plug-and-grow performance and do not plan to manage spectrum. The Chroma adds a tunable R4-R9 spectrum and an independent far-red channel run through a controller, ideal if you want to program spectrum across flowering stages and chase specific quality outcomes. If you will not actively use spectrum scheduling, the R8 is the better value; if you will, the Chroma earns its premium.
How many under-canopy lights do I need per bench?
It depends on your bench size and plant layout, so follow the manufacturer's layout guidance rather than a single rule. Both Gavita and Faven offer starter configurations built around common bench sizes such as 4x4 and 4x8, and Faven will build a custom lighting layout for larger commercial facilities. The goal is even, moderate supplemental coverage of the lower canopy, so plan fixture spacing around your actual rows and the gaps where bars can physically sit.
Should an under-canopy light be full-spectrum or red?
It depends on your top light. A red-heavy under-canopy fixture like the Faven R8 is designed to complement a full-spectrum top light by filling the red the lower canopy lacks, which many commercial growers prefer. A full-spectrum under-canopy fixture like the Gavita acts more like a complete light placed down low. The Chroma lets you choose by tuning its spectrum. If your top light is already full spectrum, a red-forward complement is often the more targeted choice, but both approaches work.
Do you need a controller for under-canopy lighting?
Not always. The Faven R8 needs only a simple 0-10V dimmer and no dedicated controller, and the Gavita is dimmable on its own while also supporting commercial controllers if you use one. The Faven Chroma, however, is designed to run through a controller such as the CX2 or GrowFlux to access its tunable spectrum and far-red scheduling. So if you want set-and-forget simplicity, the R8 avoids the controller question entirely; if you want programmable spectrum, plan for the controller as part of the Chroma system.
Is under-canopy lighting worth it for home growers?
Sometimes, but less often than for commercial rooms. A home grower with tall, dense plants or a trellised, sea-of-green setup whose lower buds turn to larf can benefit, and these fixtures are sold to home growers as well as commercial ones. But a small grow with good light penetration, short plants, or a sparse canopy may see little return for the added cost and labor. Be honest about whether your lower canopy is genuinely light-starved before investing, and if it is not, your money is better spent elsewhere.
Whichever route fits your room, under-canopy fixtures from Gavita and Faven, along with the stands, controllers, cabling, and meters to run them well, live in the Modern Farms catalog under Environmental Control, and our team is glad to help you decide whether under-canopy lighting suits your grow at all before sizing a system. Light is the foundation of every harvest, so start with the big picture in our grow light buying guide, follow the whole grow with our week-by-week grow guide, and get the stage-by-stage detail in our flowering guide. Because, as always, we don't upsell.
For informational and educational purposes only. This article is general horticultural guidance and is not legal advice. Cannabis cultivation laws vary by country, state and locality, and growing cannabis may be illegal where you live. Always understand and comply with the laws and regulations that apply to you before growing any cannabis plant.