What is the difference between Barrina T5 and T8 Grow Light?

Choosing the right grow light can make or break your indoor garden. If you’re stuck between the Barrina T5 vs T8 grow light models, here’s what you need to know: the T8 delivers over 2× the PPFD of a T5 at the same distance, making it far better for light-hungry plants. But the T5’s slim design and lower wattage make it perfect for tight spaces and delicate seedlings.

Both are full-spectrum LEDs, but one offers higher intensity, while the other is more suitable for a wider range of setups. If you’re unsure which is the better match for your grow shelf, tent, or greenhouse cabinet, this side-by-side comparison will give you clear answers.

No guesswork—just the actual specs and real-world performance to help you choose with confidence

What does T5 mean in grow lights?

T5 grow lights refer to a type of fluorescent or LED tube light that measures 5/8 of an inch in diameter. The “T” stands for tubular, and the number 5 represents the eighths of an inch—so a T5 tube is slimmer than its T8 counterpart. Due to their slim design, T5 lights are popular in indoor gardening, where space is limited. They’re often used on seedling racks, plant shelves, or greenhouse cabinets, especially in setups where lights must be close to the plants.

Most T5 grow lights available today use LED technology, which makes them energy-efficient and cool to the touch. That cooler operation means you can position them just inches above tender seedlings or delicate plants without burning leaves. Each light bar typically uses around 10 watts and emits full-spectrum light. It contains both blue and red wavelengths that support all stages of plant growth—from germination to early vegetative growth.

You’ll often see growers using multiple T5 bars side by side to create even light coverage across a shelf. Their lightweight, low-profile design makes it easy to mount under shelves or inside cabinets. Since they’re lower in intensity than stronger grow lights, they’re ideal for leafy greens, herbs, microgreens, and clones that don’t require intense light to thrive. If you’re starting small or need a gentle light for propagation, T5 lights are a practical and affordable choice.

What does T8 mean in grow lights?

T8 grow lights use a tube that’s 8/8 of an inch—or exactly 1 inch—in diameter, making it thicker than T5 tubes. Like the T5s, most modern T8 grow lights use LED technology to deliver bright, efficient, full-spectrum light suitable for various plants. The larger diameter doesn’t just affect the look—it usually means the light fixture is more powerful. Each 2ft Barrina T8 grow light bar uses about 24 watts and delivers noticeably higher intensity than a T5 of the same length.

That extra power makes T8 lights a solid choice for growers who need stronger illumination. They’re especially useful for mid-to-high light plants, such as succulents, carnivorous species, peppers, or tomatoes. Due to their higher output, T8 lights can be mounted slightly higher above the canopy while still delivering sufficient PPFD for robust growth. You’ll often find T8 lights hung in grow tents, above greenhouse benches, or across wider shelving units.

Another bonus is that many T8 fixtures have a built-in reflector, which directs more of the light downward where your plants need it. This design enhances intensity without requiring additional wattage. While bulkier than T5s, they’re still relatively low-profile and easy to mount using clips or foam tape. For growers who want to push their plants through every stage—from seedling to flowering—a T8 setup delivers the brightness and coverage needed for stronger development.

Diameter

The main physical difference between T5 and T8 grow lights lies in their tube thickness. T5 tubes measure 5/8 of an inch (about 0.625 inches) in diameter, while T8 tubes are 1 inch thick. That might sound small, but the difference becomes noticeable when space is limited. T5 lights have a slimmer, sleeker profile, making them easier to fit under shelves, inside cabinets, or stacked growing systems. You can mount them close together or closer to the plants, using minimal vertical space.

T8 lights, on the other hand, require a bit more space. The added thickness gives them a sturdier feel and makes them slightly more resistant to wear and tear. However, in tight spaces—especially where headroom is limited—that 1-inch tube can restrict how close the light can be placed above the plants. If you’re working with compact shelves or multi-level racks, T5 lights usually offer a more flexible fit.

Light Output

T5 and T8 grow lights use full-spectrum LEDs designed for indoor plant growth but differ slightly in brightness and intensity. A single 2ft T5 light typically uses around 10 watts and produces about 90–100 μmol/m²/s of PPFD when placed 8 inches above a plant. In contrast, a 2ft T8 uses 24 watts and delivers roughly 210 μmol/m²/s at the same distance. That means a single T8 bar can emit more than twice the usable light for photosynthesis compared to a T5.

This difference is particularly important when growing plants that require abundant light, such as succulents, tomatoes, or flowering plants. The higher intensity from a T8 can penetrate deeper into plant foliage and support better development across all stages, including blooming and fruiting. Meanwhile, the T5’s gentler output makes it safer for delicate plants and seedlings that might get scorched under stronger lights.

Regarding visible brightness, T5 tubes emit approximately 1100 lumens each, while T8s produce closer to 2000–2500 lumens per tube. Although lumens aren’t the most accurate way to measure grow light performance (since they measure light visible to humans, not necessarily useful to plants), they still indicate that T8s are brighter overall. Both lights maintain a balanced spectrum around 5000K, producing a natural white glow with good color rendering. This spectrum includes enough red and blue wavelengths to support healthy growth from seed to harvest.

Due to its strength, the T8 can illuminate a larger area or allow you to use fewer fixtures to achieve the same PPFD target. On the other hand, the T5 is better suited for creating even coverage over small trays, where you can place the light very close without overwhelming the plants.

Energy Efficiency

Even though the Barrina T8 lights use more power per tube—24 watts compared to the T5’s 10 watts—they’re more efficient in terms of usable plant light. Each T8 bar produces approximately 210 μmol of PPFD, equivalent to roughly 8.8 μmol per watt. The T5, while using less electricity, produces approximately 91 μmol at 10 watts, resulting in slightly lower efficiency when considering light output per watt used across a wider area.

The T8’s built-in reflector also helps boost efficiency by directing more light downward onto your plants, reducing waste. The T5 doesn’t include a reflector, so more light can scatter—unless you work in a very reflective or enclosed grow space.

When comparing full setups, the T8 system draws 144W for a 6-pack, while the T5 setup draws 80W for an 8-pack. While the T5 uses less power overall, you might need more of them to achieve the same brightness, which can balance out or even increase the total wattage. Both are energy-saving compared to older grow light types, but if your goal is maximum plant light per watt used, the T8 pulls slightly ahead.

Cost

T5 grow lights are the more affordable option upfront. An 8-pack of Barrina 2ft T5 lights typically costs between $50 and $70, which is approximately $ 6.25–$ 8.75 per tube. That makes them popular for growers who want to cover a wide area on a tight budget, especially for seedling racks or propagation shelves.

T8 lights cost a bit more, usually $70–$100 for a 6-pack. That works out to about $12–$16 per light bar. Although you’re paying more per tube, each T8 delivers stronger light output, so you may need fewer of them to achieve the same plant coverage, which can balance the total cost.

When you look at cost per watt, the T8 sometimes comes out cheaper. A 144W T8 kit at $72 is about $0.50 per watt, while an 80W T5 kit at $60 is around $0.75 per watt. So, while the T5 saves money upfront, the T8 may offer more value in the long term.

Barrina T5 Vs T8 LED Lifespan

Both the Barrina T5 and T8 LED grow lights are rated to last up to 50,000 hours, which translates to several years of regular use. That’s based on running them continuously, 24/7, though most growers run lights for 12 to 16 hours daily. With that kind of schedule, you can expect many seasons of use before needing replacements.

Each light is built with an aluminum housing that acts as a heat sink, helping keep temperatures low and preserving the LED lifespan. Most users report reliable performance even after years of daily use. While occasional failures, such as dimming or single diode issues, can occur, these are rare and often covered under Barrina’s 2-year warranty.

Real-world experiences suggest that the lights may lose brightness after several thousand hours, especially under heavy, non-stop use. Still, the T5 and T8 models are considered long-lasting options that won’t require frequent replacement, unlike older fluorescent tubes.

Application

T5 grow lights work best in compact setups with limited space or for plants that prefer lower light. Their slim profile and gentle output make them ideal for seed starting, propagation trays, and low- to medium-light plants, such as herbs, lettuce, or microgreens. You can mount them just a few inches above your plants without the risk of light burn, which is perfect for multi-shelf racks or greenhouse-style cabinets. Many growers use several T5 bars per shelf to spread light evenly across trays or collections of houseplants.

T8 lights are better suited for plants needing more intensity or larger growing areas. With higher output and stronger PPFD, they’re suited for flowering plants, fruiting vegetables, succulents, and carnivorous species that thrive under brighter light. You’ll often see T8 bars used in grow tents, hydroponic setups, or wider shelving systems where they can be hung overhead. The added strength lets you position them further from the plant canopy while delivering effective light.

If you’re growing a mix of plants, some people use T5s for starting seeds and clones and then move the plants under T8s for the main growing phase. Matching the light type to your space and plant needs makes the biggest difference.

Other Considerations

Beyond brightness and cost, a few extra factors can help you decide between Barrina T5 vs T8 grow lights. Thanks to their LED design, heat output is minimal in both, but the T8 runs a little warmer due to its higher wattage. Still, it’s not hot enough to harm nearby plants—some users even report plants touching T8 tubes without damage.

Both models are simple to install. They come with mounting clips, adhesive pads, and linkable cords. The T5 lights can be daisy-chained up to 16 units, while T8s support up to 10 in a row. This makes cable management easy, especially when setting up multiple lights across shelves or tents.

In terms of build, both are sturdy, with aluminum housings and protective plastic covers. The T8’s built-in reflector adds extra durability and light direction. If you need lights that are quick to set up, easy to expand, and low-maintenance, either option works well—it just depends on how much light your plants need.