Best 1000 Watt LED Grow Lights: Top 9 Picks (November 2026)
The best 1000 watt LED grow lights include the MARS HYDRO TS1000 150W Grow Light for balanced tent coverage, the Spider Farmer SF1000 LED Grow Lights for quiet 2 x 2 tents, and the MARS HYDRO 300W TSW2000 Led Grow Light for 3 x 3 flower areas.
On this page (7 sections)
- Which 1000 watt LED grow light is best overall?
- What does actual wattage mean on a 1000W LED grow light?
- The 9 best 1000 watt LED grow lights
- How should you choose a full-spectrum LED grow light?
- How many watts do plants need?
- How should you set up a 1000 watt LED grow light?
- Verdict: which best led grow lights 1000w should you buy?
The best 1000 watt LED grow lights are not necessarily 1000W fixtures in actual use. The MARS HYDRO TS1000 draws 150W, the Spider Farmer SF1000 draws 100W, and the Beelux 1000W model lists 110W operating power.
That gap between a name and a real draw changes every practical decision that follows. It affects how much power you plan for on a circuit, how much heat to expect in a small tent, and how many fixtures a canopy may need.
A model name can come from an HPS replacement class, a product family, or a marketing power label. None of those labels tells you the electricity the panel actually uses while it runs.
Checking actual wattage first gives you an honest basis for comparison. You can then weigh coverage, spectrum, controls, and cooling against the plants you plan to grow.
For a clearer starting point, read our guide to how many watts for a grow light. It helps separate the label from the load before you narrow the field.
We compared the stated wattage, coverage, spectrum, controls, cooling and setup details for these 9 picks. Our score weighs specs, features and buyer feedback against what you're shopping for.
That approach suits home growers who care about running costs as much as plant response. It also helps buyers avoid paying for headline numbers that the fixture will never draw.
Small tents, shelves and supplement lighting all benefit from this kind of care. Matching real power to a real canopy is the quickest way to shortlist sensibly.
As you read each pick below, keep the stated footprint beside the actual wattage. The pairing tells you more than either figure on its own.
Our picks at a glance
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Best for 3 x 3 flower areasMARS HYDRO 300W TSW2000 Led Grow Light
9.5/10 our score
See it on Amazon
- 4
Check itSpider Farmer SF1000D LED Grow Light
Best for a simple 2 x 2 setup - 5
Best for long shelvesCheck it - 6
Check itUallhome 2 Pack LED Grow Light Panel
Best for supplemental panels - 7
Check itKINGPLUS KingLED KING1000 Grow Light for Indoor
Best for switch-based control - 8
Check itBeelux 1000w LED Grow Light for Indoor
Best for a wide stated footprint - 9
Check itKINGPLUS KingLED KING2000 Grow Light for Indoor
Best for medium tent coverage
Which 1000 watt LED grow light is best overall?
The MARS HYDRO TS1000 is the best overall choice for many small and medium indoor setups because it combines 150W actual power, a 2.5 x 2.5 ft preferred footprint, dimming and a fanless design. Its 3 x 3 ft maximum coverage gives you room to adjust as the canopy changes.
That preferred footprint matters in daily use. It sets a sensible centre for a compact tent, while the wider maximum works better when plants are shorter or more evenly spaced.
Dimming from 0 to 100% gives you control through the cycle. You can start gently for seedlings, raise output as growth builds, and back off if leaves show stress.
The fanless build will suit living spaces where noise matters. You trade active fan cooling for quieter running, so ventilation elsewhere in the tent still needs attention.
The Spider Farmer SF1000 is close behind for a smaller tent. It draws 100W, covers 2 x 2 ft during flowering and 3 x 3 ft during vegetative growth, and has a dimming knob.
Its smaller flowering footprint is the key trade-off. It fits a tight 2 x 2 space well, but a wider canopy may need a second fixture or a higher-output model.
Both picks reward careful hanging and spacing. Centre the panel, keep the canopy even, and change height or dimming in small steps as plants respond.
| Product | Best for | Actual wattage | Coverage | Spectrum | Our score |
|---|---|---|---|---|---|
| MARS HYDRO TS1000 150W Grow Light | balanced tent coverage | 150W | 2.5 x 2.5 ft preferred, 3 x 3 ft maximum | Full spectrum with red IR, white, red and blue ranges | 9.7 |
| Spider Farmer SF1000 LED Grow Lights | quiet 2 x 2 tents | 100W | 2 x 2 ft flowering, 3 x 3 ft vegetative | 9.6 | |
| MARS HYDRO 300W TSW2000 Led Grow Light | 3 x 3 flower areas | 300W | 3 x 3 ft flower, 4 x 4 ft veg | Full spectrum with red IR, white, red and blue ranges | 9.5 |
| Spider Farmer SF1000D LED Grow Light | a simple 2 x 2 setup | 100W | Blue, 660–665nm, 3000K, 5000K and IR | 9.5 | |
| Barrina Plant Grow Lights | long shelves | 9.4 | |||
| Uallhome 2 Pack LED Grow Light Panel | supplemental panels | 4 x 4 ft stated coverage | 9.3 | ||
| KINGPLUS KingLED KING1000 Grow Light for Indoor | switch-based control | 100W maximum compatible source wattage | 2 x 2, 2 x 3 and 2 x 4 ft tents | 9.3 | |
| Beelux 1000w LED Grow Light for Indoor | a wide stated footprint | 4 x 4 ft grow area | 9.2 | ||
| KINGPLUS KingLED KING2000 Grow Light for Indoor | medium tent coverage | 200W | 3 x 3, 3 x 4 and 3 x 5 ft tents | 9.1 |
What does actual wattage mean on a 1000W LED grow light?
Actual wattage is the electrical power the fixture uses while operating. It gives you a more useful comparison than a name such as KING1000 or Beelux 1000W.
The KINGPLUS KING1000 has a 1000W product name but lists 100W as its maximum compatible light source wattage. Beelux names its fixture a 1000W LED grow light while listing 110W operating power.
Those numbers are much closer to what you need for planning energy use.
The MARS HYDRO TS1000 uses 150W with 354 LEDs, while the Spider Farmer SF1000 uses 100W. The TSW2000 is the highest-output panel in this group at 300W.
Actual wattage still doesn't tell you everything. Coverage, hanging distance, spectrum, canopy density and the plant's growth stage also affect results.
If you're comparing smaller fixtures, see our Top 7 Watt LED Grow Light guide for a separate look at low-power options.
The 9 best 1000 watt LED grow lights
The best model depends on your canopy size and how much control you want. These products are ordered by score, with the highest-scoring option first.
MARS HYDRO TS1000 150W Grow Light: Best for balanced tent coverage
- 150W actual power
- 2.5 x 2.5 ft preferred coverage
- 3 x 3 ft maximum coverage
- Dimmable and daisy-chain capable
The TS1000 gives small and medium grow spaces a clearly stated 150W fixture with dimming, fanless cooling and a broad full-spectrum range.
Pros
- Dimmable from 0 to 100%
- 120-degree beam angle
- Supports daisy chaining
Cons
- RJ12 connector for daisy chaining is separate
- 150W is not the same as 1000W actual draw
The MARS HYDRO TS1000 is the strongest fit for a compact tent that needs more than a basic 100W panel. It uses 150W of power and is designed for a 2.5 x 2.5 ft area, with 3 x 3 ft listed as its maximum coverage.
The dense centre and sparser sides help keep light more even from middle to edge. That suits a canopy that fills the footprint rather than a single tall plant in the middle.
Its full-spectrum range includes 730–740nm red IR, 3200–4200K, and 5200–6800K ranges. The mix is meant to support growth from seed through flower without changing lamps.
The fixture uses a 120-degree beam angle and an aluminum, fanless design. The wide angle spreads light across the tent, while the aluminum body sheds heat quietly.
The external driver supports dimming from 0 to 100%. MARS HYDRO also lists daisy chaining for up to 50 TS-series lights, although the RJ12 connector must be bought separately.
Set it up by centering the bar over the canopy and using the preferred 2.5 x 2.5 ft footprint as your first guide. Raise or dim gradually for seedlings, then increase as the canopy widens.
This is the best choice if you want a clear 150W fixture with flexible control. It is too small to treat as a true 1000W electrical replacement, so compare the stated coverage with your actual canopy.
Spider Farmer SF1000 LED Grow Lights: Best for quiet 2 x 2 tents
- 100W actual power
- 2 x 2 ft flowering coverage
- 3 x 3 ft vegetative coverage
- Dimmable fanless design
The SF1000 is a compact 100W fixture for small tents. Its full-spectrum LEDs, dimming knob and fanless aluminum design suit growers who want quiet operation.
Pros
- 5-year warranty
- Dimmable
- Full spectrum for all growth stages
Cons
- Smaller flowering footprint than larger fixtures
- Actual draw is 100W
The Spider Farmer SF1000 is a compact 100W full-spectrum LED fixture for small tents and indoor plant spaces. Its stated coverage is 2 x 2 ft during flowering and 3 x 3 ft during vegetative growth.
That split footprint reflects how light need changes through the cycle. Vegetative plants can use the wider 3 x 3 ft area, while flowering usually needs the tighter 2 x 2 ft zone for stronger intensity.
The 2026 version uses an edge-focused diode layout, a dimming knob and compatibility with GGS controllers. The edge focus aims to even out light at the canopy borders, where panels often fall short.
Its spectrum combines white, blue, red and IR light, including 3000K, 5000K, 660nm and IR 760nm. The cooler 5000K portion supports vegetative growth, while the warmer and red portions suit later stages.
The fanless aluminum design keeps operation quiet. Spider Farmer lists a 5-year warranty, and the included light kit makes it suitable for a straightforward hanging setup.
Choose it when your priority is quiet operation and simple dimming in a small tent. For 3 plants, use the canopy size rather than the product name to decide if one fixture is enough.
Our guide explains how many lights for 3 plants.
MARS HYDRO 300W TSW2000 Led Grow Light: Best for 3 x 3 flower areas
- 300W actual power
- 3 x 3 ft flowering coverage
- 4 x 4 ft vegetative coverage
- Dimmable and fanless
The TSW2000 is the higher-output choice here for a larger tent. Its 300W draw, 120-degree reflector and 0 to 100% dimming suit a 3 x 3 ft flowering area.
Pros
- Largest actual wattage among the first three picks
- 5-year warranty
- Supports daisy chaining
Cons
- Larger and heavier than compact fixtures
- May be more light than a small plant shelf needs
The MARS HYDRO TSW2000 is the high-output option for a larger growing area. It consumes 300W, covers 3 x 3 ft for flowering and 4 x 4 ft for vegetative growth.
That higher draw separates it from the 100W and 150W panels in this roundup. It suits growers who found a smaller fixture left the outer canopy too dim during flower.
Its 120-degree reflector is designed to spread light across the canopy. The wider throw helps cover a 3 x 3 ft flowering footprint without forcing the fixture very low.
The full-spectrum mix includes red IR, white, red and blue ranges, and the external driver allows dimming from 0 to 100%. Dimming is useful here because a 300W panel can be stronger than young plants need.
The fanless aluminum system is listed with daisy-chain support for up to 50 lights. The power supply works with 120VAC, 240VAC and 277VAC systems.
Pick it when a 100W or 150W panel would leave too much canopy uncovered. Its 21.2 x 19.7 x 3.7 in size and 7.7 lb weight call for a more deliberate hanging plan.
Spider Farmer SF1000D LED Grow Light: Best for a simple 2 x 2 setup
- 100W actual power
- 3 x 3 ft vegetative footprint
- 2 x 2 ft flowering footprint
- Samsung LM301B diodes
The SF1000D keeps the footprint compact while covering seedlings, vegetative plants and flowering plants with a full-spectrum mix. It is a practical match for a small tent.
Pros
- 5-year warranty
- Waterproof LED board
- Zero-noise fanless design
Cons
- No coverage larger than 3 x 3 ft is stated
- Actual draw is 100W
The Spider Farmer SF1000D is a simple 100W panel for a 2 x 2 tent. It covers 3 x 3 ft during vegetative growth and 2 x 2 ft during flowering.
That footprint makes it a natural fit for compact tents and shelves. It suits seedlings, herbs and a small flowering canopy more than a wide, dense canopy.
Its full-spectrum mix includes blue light, 660–665nm light, 3000K, 5000K and IR. The blend covers vegetative and flowering needs within one fixture, so you do not need to swap lamps between stages.
The panel uses Samsung LM301B diodes, a waterproof LED board and a large aluminum heat sink. The waterproof board is a practical plus where misting or spills are part of routine care.
The zero-fan design keeps the fixture quiet. Spider Farmer lists a 5-year warranty, and the package includes a light kit.
Choose the SF1000D if you want a compact panel with a broad spectrum and no fan noise. Its 100W draw is easier to compare with the SF1000 than with products whose names use 1000W.
The trade-off is coverage. If your canopy outgrows 2 x 2 ft in flower, plan for a second fixture or step up to a larger model.
Barrina Plant Grow Lights: Best for long shelves
- 6-pack of 4 ft strips
- 5000K full-spectrum daylight white
- 252W total consumption
- Link up to 6 strips
Barrina is a shelf and rack solution rather than a single square panel. Six 4 ft strips spread light across long growing areas and include mounting hardware.
Pros
- Long 4 ft fixtures
- 5000K full-spectrum white light
- Installation hardware included
Cons
- 252W total consumption
- Strip layout is less suited to one small tent ceiling
Barrina takes a different approach from the square panels in this roundup. You get 6 strips that are each 4 ft long, with 5000K full-spectrum daylight white light for shelves, racks, seedling areas and longer growing spaces.
The long format suits spaces where a single square panel would create hot spots and dark corners. Six strips can run along racks or above benches, giving each shelf its own even row of light.
The set consumes 252W in total and includes 3 power cords with switches, 5 connecting cords, 6 small connectors, clips, tape and cable ties. The strips can link up to 6 units in a series.
That included hardware matters in daily use. You can mount the strips in minutes, group them by shelf, and switch sections separately rather than lighting a whole area at once.
The aluminum shell uses a V-shaped reflector, and Barrina lists a maximum output of 2100 lumens. The reflector pushes light down toward the plants instead of letting it spill sideways.
Choose Barrina when your growing area is long or divided into several shelves. It is less convenient if you need one centered panel above a small canopy.
Uallhome 2 Pack LED Grow Light Panel: Best for supplemental panels
- 2-panel set
- 12 x 12 x 1 in panels
- White, blue, red, UV and IR LEDs
- Hanging kit included
The Uallhome pair works well when one overhead fixture leaves darker areas. The slim aluminum panels can serve as supplemental side lighting or a compact two-panel arrangement.
Pros
- Two panels for flexible placement
- Full-spectrum light from UV through IR
- Low-heat design
Cons
- Not waterproof
- 90-day manufacturer warranty
The Uallhome 2 Pack suits growers who need two light sources instead of one overhead panel. Each aluminum panel measures 12 x 12 x 1 in, and the set includes a hanging kit.
Two slim panels give you placement choices that one fixed fixture cannot match. You can run them side by side over a compact canopy or split them to cover separate shelves.
The panels use white, blue, red, UV and IR LEDs for a full-spectrum mix. That range supports vegetative growth and flowering within the same pair of fixtures.
Uallhome describes the pair as suitable for a 4 x 4 ft grow tent, with low heat and low power use. Low heat helps when plants sit close under the panels or when tent ventilation is limited.
The panels are not waterproof, so keep them in an indoor space protected from splashes. The package includes the light kit and a user manual, and the manufacturer warranty is 90 days from purchase.
Use these panels as overhead lights for a compact arrangement or as supplemental side lighting where one fixture leaves darker foliage. The two-panel layout also gives you more placement choices than one fixed strip.
KINGPLUS KingLED KING1000 Grow Light for Indoor: Best for switch-based control
- Fits 2 x 2, 2 x 3 and 2 x 4 ft tents
- VEG and BLOOM switches
- Built-in fans
- Full spectrum
The KING1000 uses separate VEG and BLOOM switches instead of dimming. Its stated tent sizes suit one to several light or moderately dense plants in a compact growing space.
Pros
- VEG and BLOOM modes
- Built-in fans
- Hanging kit included
Cons
- Not dimmable
- The 1000W name does not describe actual draw
The KINGPLUS KING1000 fits 2 x 2, 2 x 3 and 2 x 4 ft tents. Its VEG and BLOOM switches let you choose between the two modes, but the fixture is not dimmable.
Those physical switches suit growers who prefer simple stage changes over dials or apps. Use VEG for seedlings and early growth, then add BLOOM as plants mature and need stronger light.
The full-spectrum setup uses blue 460nm, red 660nm and white 3000K–5000K light. The mix covers germination, vegetative growth, flowering and fruiting without separate lamps.
Built-in fans move air through openings in the LED panel, which may suit a buyer who prefers active airflow around the fixture. The trade-off is fan noise and moving parts, unlike the fanless panels elsewhere in this roundup.
The package includes adjustable hanger rope, a metal hanging kit, an LED grow light and a power cord. The fixture measures 12.2 x 8.46 x 1.85 in.
The KING1000 is best for someone who wants physical mode switches instead of a dimming knob. Read the stated coverage closely because the 1000W name does not represent actual electrical draw.
Beelux 1000w LED Grow Light for Indoor: Best for a wide stated footprint
- 110W operating power
- 4 x 4 ft grow area
- Dual chips and dual switches
- Aluminum cooling back
Beelux uses the 1000W label to describe an HPS replacement class, while its operating power is 110W. It suits buyers who want a broad stated footprint and VEG and FLOWER controls.
Pros
- 4 x 4 ft stated grow area
- Dual chips and dual switches
- 2-year warranty
Cons
- Not waterproof
- Actual operating power is 110W
Beelux calls this a 1000W LED grow light, but its stated operating power is 110W. The fixture is designed for a 4 x 4 ft grow area and uses dual chips with full-spectrum light.
That 110W figure is the number to use for planning power and heat. The 1000W label refers to the HPS replacement class, not the electricity the panel draws.
The panel has dual switches for plant stages and an aluminum back cover for heat dissipation. Dual chips and switches give you separate choices for vegetative and flowering phases.
The included items are a power cord, steel hanging kits, an adjustable rope and the LED grow light. The adjustable rope helps you change height as plants grow, without reworking the whole mount.
Beelux lists a 5130-lumen maximum output and a 2-year warranty. It also states that the fixture is for indoor use and is not waterproof.
Choose it if the 4 x 4 ft stated area and adjustable hanging setup fit your plan. Check your room size and plant spacing carefully because a broad claimed footprint does not remove the need for even canopy placement.
KINGPLUS KingLED KING2000 Grow Light for Indoor: Best for medium tent coverage
- Fits 3 x 3, 3 x 4 and 3 x 5 ft tents
- 200W actual power
- VEG and BLOOM switches
- Built-in fans
The KING2000 expands the switch-based KINGPLUS design for medium tents. Its 200W draw and larger stated coverage make it a better fit than the KING1000 for a wider canopy.
Pros
- Fits 3 x 5 ft tents
- VEG and BLOOM modes
- Hanging kit included
Cons
- Not dimmable
- Built-in fans add moving parts
The KINGPLUS KING2000 expands the switch-based design for medium tents. It fits 3 x 3, 3 x 4 and 3 x 5 ft tents and uses 200W of power.
That larger footprint makes it a step up from the KING1000 for wider canopies. It suits growers whose plants spread beyond a compact 2 x 4 ft area during flower.
Its full-spectrum mix combines blue 460nm, red 660nm and white 3000K–5000K light. Separate VEG and BLOOM switches let you change the mode, but the fixture is not dimmable.
Switch-based control is simple, but it is less fine grained than a dimmer. You adjust intensity mainly by choosing a mode and changing hanging height or plant spacing.
Built-in fans move air through the LED panel. The package includes adjustable hanger rope, a metal hanging kit, an LED grow light and a power cord.
The KING2000 is a better fit than the KING1000 when your canopy is wider or deeper. Its 15.35 x 11.02 x 1.85 in body is still compact, but the 6 lb weight deserves a secure hanging point.
How should you choose a full-spectrum LED grow light?
Choose a full-spectrum LED by actual wattage, usable coverage and control range first. Spectrum matters, but a broad spectrum cannot compensate for a fixture that is too weak or too small for the canopy.
A full-spectrum fixture may combine white, blue, red, IR and sometimes UV light. The Spider Farmer SF1000D lists blue, 660–665nm, 3000K, 5000K and IR, while the Uallhome panels list UV, IR, red, blue and white LEDs.
Full spectrum also doesn't mean every fixture produces the same amount of useful light. Compare the stated footprint and actual power, then adjust the hanging height to suit seedlings, vegetative plants or flowering plants.
For a deeper explanation of the term, read What Is a Full Spectrum Grow Light?. If you want a list focused on spectrum rather than model wattage, see Best Full Spectrum Grow Light.
How many watts do plants need?
Plants need enough light across the whole canopy, so wattage is only a starting point. A 100W fixture may work for a compact 2 x 2 flowering area, while a 300W fixture is better matched to the TSW2000's stated 3 x 3 ft flowering coverage.
Coverage and wattage need to be read together. A low-wattage panel stretched over a wide area may leave edges dim, while a higher-wattage panel over a tiny canopy may be more than young plants need.
Use lower intensity for seedlings and increase it gradually as plants grow. Dimming helps with this when available, as on the MARS HYDRO TS1000, MARS HYDRO TSW2000 and Spider Farmer SF1000.
Gradual change matters because plants respond to shifts in light over days. Small steps let you watch leaf colour and posture, then decide whether to raise output or lift the fixture.
Fixtures without dimming need more adjustment through hanging height and plant spacing. The KINGPLUS models use VEG and BLOOM switches, so their control is based on mode selection rather than a continuous intensity range.
Canopy density also changes the answer. Light, open growth can use a wider footprint, while dense foliage may need closer spacing or extra side light.
Avoid comparing a 1000W product name with a 100W actual draw as if they were equal electrical loads. Check the operating or source wattage, then compare coverage and the number of fixtures needed.
How should you set up a 1000 watt LED grow light?
Start by centering the fixture over the canopy and leaving enough space for the stated footprint. A rectangular Barrina strip set needs a shelf layout, while a square panel such as the SF1000 needs centered placement over the plants.
Hang the fixture securely, keep cords away from water and avoid looking directly at bright LEDs. The Beelux model is listed for indoor use only and is not waterproof, while the Uallhome panels also list a non-waterproof design.
Use a dimmer when one is available. Start seedlings at lower intensity, then increase light as the plants develop.
Watch for stretched growth, pale leaves or signs of excess light, and change one factor at a time.
Keep the growing area ventilated and inspect the fixture, cords and hanging hardware during routine care. Fanless models reduce noise, while KINGPLUS models use built-in fans to move air through the panel.
Verdict: which best led grow lights 1000w should you buy?
The MARS HYDRO TS1000 is the best all-around pick when you want 150W actual power, dimming and 2.5 x 2.5 ft preferred coverage. Choose the Spider Farmer SF1000 for a quieter 100W fixture in a small tent.
Pick the MARS HYDRO TSW2000 for a 3 x 3 ft flowering area and 300W actual power. That higher output suits a larger canopy that a 100W or 150W panel would struggle to cover evenly.
Choose Barrina for long shelves, Uallhome for two supplemental panels and Beelux when its 4 x 4 ft stated area fits your layout. Each of those picks solves a different shape problem rather than chasing the same square footprint.
For switch-based control, choose the KINGPLUS KING1000 for a compact tent or the KINGPLUS KING2000 for a wider 3 x 3 to 3 x 5 ft space. The KING2000 adds power and coverage, while both keep control simple with VEG and BLOOM switches.
Always compare actual wattage before treating a product name as an electrical rating. That one check will steer you toward the right fixture for your tent, shelves and plants.
Our top 3 picks at a glance
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Best for 3 x 3 flower areas
MARS HYDRO 300W TSW2000 Led Grow Light
9.5/10 our score
See it on Amazon
Frequently asked questions
What does 1000W mean on an LED grow light?
A 1000W label often describes an HPS replacement class or model name, not the electricity the LED fixture uses. The Beelux 1000W model lists 110W operating power, while the KING1000 lists 100W maximum compatible source wattage.
Check actual operating wattage before comparing energy use.
What is the best actual wattage for a 3 x 3 grow tent?
A 3 x 3 tent needs enough light for the plant type, growth stage and canopy density. The MARS HYDRO TSW2000 uses 300W and is listed for 3 x 3 ft flowering coverage.
Smaller 100W fixtures can suit lighter or less demanding layouts, but coverage and hanging height still matter.
Are full spectrum LED grow lights 1000W better?
Full spectrum describes the mix of light rather than the fixture's real power. The Spider Farmer SF1000 and SF1000D use 100W actual power with full-spectrum ranges, while the MARS HYDRO TS1000 uses 150W.
Compare spectrum, coverage and real wattage together.
How high should an LED grow light hang?
Start with the light's instructions, then watch the plants for signs of excess or insufficient light. Use dimming when available, increase distance if leaves show light stress, and lower intensity or distance gradually for seedlings.
Plant height, canopy density and fixture power all change the useful hanging distance.
