9 Best Ceramic Metal Halide Bulb (November 2026)
The best ceramic metal halide grow bulbs include the Bluex Bulbs for M58 ballast fixtures, the Bluex Bulbs 3 Pack MP100/U/MED 100 Watt for 100-watt medium-base setups, and the PROTOPIA CMH 315W 4000K Grow Light Bulb for balanced indoor growth.
On this page (5 sections)
The best ceramic metal halide bulb for most indoor growers is the PROTOPIA CMH 315W 4000K, which pairs 315 watts with a 4000K spectrum, an E26 base and a color rendering index of 98.
That mix suits both vegetative and flowering phases without changing bulbs midway. It gives more output than the 100-watt bulbs here without the extra planning needed for larger lamps.
Choose the GRUOTVSZAK 315W 3000K 2-pack for warmer flowering light, or step up to 600W and 1000W lamps for larger areas. Higher wattage covers more canopy, but needs a fixture, wiring and space rated for that load.
Ceramic metal halide bulbs are a type of metal halide lamp for high-intensity discharge lighting. In practice, ballast and fixture shape the result as much as the bulb itself.
The right choice depends on more than wattage. A bulb with the wrong ANSI code or base will not run correctly, however strong its stated output looks.
Match ballast code, base, fixture type, color temperature and available space. Check the label on your existing ballast first, then confirm socket size and reflector clearance.
Color temperature comes after fit. A 4000K lamp sits in the middle, a 3000K lamp leans warm for flowering, and a 6000K lamp leans cool for vegetative growth.
Operating life matters for scheduling too. Lamps here range from 5,000 hours to more than 20,000 hours, so a shorter-lived bulb may need a replacement plan.
If you are weighing HID systems against newer options, our guide to HID vs LED grow lights explains the differences in heat, efficiency, control and bulb replacement.
Our picks at a glance
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1
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2
Best for 100-watt medium-base setupsBluex Bulbs 3 Pack MP100/U/MED 100 Watt
9.6/10 our score
See it on Amazon -
3
Best for balanced indoor growthPROTOPIA CMH 315W 4000K Grow Light Bulb
9.3/10 our score
See it on Amazon
- 4
Check itGRUOTVSZAK Protected MP100/U/MED 100 Watt Metal Halide
Best for protected outdoor-style fixtures - 5
Check itPROTOPIA 1000 Watt Vegetative Metal Halide Lamp
Best for large vegetative footprints - 6
Check itVegelumax MH 600W Metal Halide Single Ended
Best for high-lumen vegetative lighting - 7
Check itGRUOTVSZAK CMH 315W 3000K 625umol / 4200K
Best for warm full-spectrum flowering light - 8
Check itSunlite MP70/U/MED/PS 03641-SU 70-watt Protected Metal Halide
Best for low-wattage replacements - 9
Check itVegelumax MH 400W Metal Halide HID Grow
Best for 400-watt vegetative setups
The best ceramic metal halide bulbs by ballast, wattage and spectrum
The best ceramic metal halide bulb depends on your existing fixture first, then on the spectrum and wattage you want. The top picks below are ordered by score, with higher scores going to products that offer a stronger match for common grow-light needs and clearer specifications.
Our score weighs specs, features and buyer feedback against what you're shopping for. We checked the stated wattage, base, spectrum, ballast information, output and operating life, but we did not test these bulbs in person.
Bluex Bulbs: Best for M58 ballast fixtures
- 3-pack
- 250 watts
- 4000K
- 21,000 lumens
- E39 mogul base
- M58 ballast code
This 3-pack suits growers who already use M58 fixtures with E39 mogul sockets. Its 250-watt output and 4000K color temperature offer a middle ground between small lamps and high-wattage grow bulbs.
Pros
- 3-pack
- 21,000 lumens
- 15,000-hour average lamp life
Cons
- Requires an M58 ballast fixture
- Mogul base is not a medium base
Bluex Bulbs is the strongest choice when your fixture uses an M58 ballast and E39 mogul base. The 3-pack includes 250-watt metal halide bulbs with a 4000K color temperature and 21,000 lumens.
That combination fits growers who want more output than a 100-watt replacement without moving to a 600-watt or 1000-watt lamp. It can suit a medium-sized indoor area where the existing fixture already has the right socket and ballast.
The 4000K neutral white color also sits between the warmer 3000K flowering spectrum and the cooler 6000K vegetative spectrum. That makes it a balanced light for everyday plant checks, since foliage color is easier to read under neutral white light.
The ED28 clear bulbs are 8.2 in tall, so check the fixture's available space before installation. A tall bulb needs room inside the reflector, and a tight enclosure can make fitting and later removal harder.
Their stated average lamp life is 15,000 hours, which is longer than the 6000-hour operating life of the PROTOPIA 1000W lamp. That longer figure helps with planning, though real use still depends on the fixture and how often the lamp is switched.
Choose this pack when your ballast and socket already match. The E39 mogul base is not interchangeable with an E26 medium base, so measure and read the existing socket before ordering.
The 3-pack format is useful when more than one fixture uses the same format. Having spare bulbs on hand can reduce downtime if one lamp fails during a grow cycle.
Bluex Bulbs 3 Pack MP100/U/MED 100 Watt: Best for 100-watt medium-base setups
- 3-pack
- 100 watts
- 4000K
- 8,500 lumens
- E26 medium base
- M90/O ballast code
This 3-pack works for growers who need 100-watt protected metal halide bulbs with E26 medium bases. The 4000K color and 8,500-lumen output fit smaller setups and replacement needs.
Pros
- 3-pack
- E26 medium base
- 15,000-hour average lamp life
Cons
- M90/O ballast fit must be confirmed
- Not dimmable
Bluex Bulbs 3 Pack MP100/U/MED 100 Watt is a good fit for smaller setups that use an E26 medium base and M90/O ballast. Each bulb is rated at 100 watts, 4000K and 8,500 lumens.
The protected pulse-start design and 15,000-hour average lifespan suit replacement work where you want multiple bulbs available. Pulse start operation is part of the stated design, and the long average life helps when a lamp runs for many hours each day.
The 3-pack also makes sense when several fixtures use the same 100-watt format. Buying a pack can be more practical than ordering single bulbs one at a time.
Its color rendering index is 100, the highest stated value among these products. That does not make it a grow-specific CMH lamp, but it can help you see plant color clearly under the 4000K white light.
The bulb is not dimmable. That means light control comes from fixture height, spacing and on-off timing rather than a dimmer setting.
Confirm the M90/O ballast and E26 socket before ordering, especially if you're replacing a different HID bulb. A close wattage alone is not enough to guarantee a safe match.
This option suits smaller grow areas and general replacement jobs. It is less suited to large canopies that need the higher output of 315W, 600W or 1000W lamps.
PROTOPIA CMH 315W 4000K Grow Light Bulb: Best for balanced indoor growth
- 315 watts
- 4000K
- Color rendering index 98
- E26 base
- 15,000-hour operating life
This is the strongest all-around ceramic metal halide bulb in the group for growers who want a 315-watt lamp with 4000K color and a color rendering index of 98. It is intended for standard 315W CMH fixtures.
Pros
- High color rendering index
- 4000K spectrum
- 15,000-hour operating life
Cons
- Non-dimmable
- Needs a compatible 315W CMH fixture
PROTOPIA CMH 315W 4000K is the best ceramic metal halide bulb here for a balanced indoor grow setup. It uses an E26 base, produces 4000K daylight white light and has a color rendering index of 98.
The 315-watt format is a practical middle ground. It offers more power than the 100-watt bulbs, but it does not require the same high-wattage fixture planning as a 600W or 1000W lamp.
That balance makes it suitable for a single fixture over a modest canopy. Growers can raise or lower the fixture to adjust coverage, which is often the main way to manage intensity with a non-dimmable lamp.
PROTOPIA identifies this bulb for standard 315W CMH fixtures and describes it as suitable for vegetative and flowering use. Using it across both phases can simplify a setup that would otherwise need separate lamps.
Its stated operating life is 15,000 hours, and its efficiency is 110 lumens per watt. The life figure helps with long schedules, while the efficiency figure gives a sense of output per watt rather than total brightness alone.
This bulb is non-dimmable, so plan the light level through fixture height and timing rather than a dimmer. Keep the fixture at a height that spreads light evenly without creating hot spots.
The E26 base also needs to match the fixture socket. Confirm that your 315W CMH fixture takes this base before ordering, since other 315W models in this group use a PGZX18 base.
GRUOTVSZAK Protected MP100/U/MED 100 Watt Metal Halide: Best for protected outdoor-style fixtures
- 2-pack
- 100 watts
- 4000K
- 9,200 lumens
- E26 medium base
- 120 volts
This 2-pack is suited to buyers who want protected 100-watt bulbs with E26 medium bases. The 4000K color and 9,200-lumen output make it a practical replacement option where the stated ballast match is confirmed.
Pros
- Protected design
- 2-pack
- 9,200 lumens
Cons
- The title references M90 while the bullet states M102
- No warranty
GRUOTVSZAK Protected MP100/U/MED 100 Watt is a useful option when you want a protected 100-watt bulb in a 2-pack. It has an E26 medium base, 4000K white light and a stated output of 9,200 lumens.
The protected design is intended to help contain shattered glass if the arc tube breaks, and the bulb is described for open fixtures. That protection matters more where a fixture has no enclosed glass cover between the lamp and the space below.
Its 120-volt specification may help narrow the right use, but the fixture and ballast still need to match. Voltage is only one part of compatibility, so it should not replace a check of the ANSI code.
There is one compatibility detail to resolve before buying. The title references an ANSI M90 ballast, while the bullet information states compatibility with an ANSI M102 ballast.
Treat that difference as a reason to confirm the exact ballast code. Write down the code printed on your ballast and compare it with the listing before you place an order.
The 2-pack is handy for growers with two matching fixtures or for keeping one spare bulb ready. A second bulb can save time if a lamp fails during a period when plants need steady light.
This pack suits outdoor-style or general HID replacements more than a dedicated CMH grow system. Its 100-watt output is modest, so it fits smaller areas better than a large indoor canopy.
PROTOPIA 1000 Watt Vegetative Metal Halide Lamp: Best for large vegetative footprints
- 1000 watts
- 6000K
- E39 base
- Enhanced blue and violet spectrum
- 6000-hour operating life
This lamp is for large indoor grow areas that can support a 1000-watt E39 fixture. Its 6000K blue and violet enhanced spectrum is positioned for vegetative growth and tighter spacing.
Pros
- Large 1000-watt output
- 6000K spectrum
- E39 base
Cons
- 6000-hour operating life
- Requires a high-wattage fixture
PROTOPIA 1000 Watt Vegetative Metal Halide Lamp is the right pick for a large vegetative footprint that can support a 1000-watt E39 fixture. Its 6000K spectrum is described as enhanced in blue and violet.
The cooler color is aimed at vegetative growth, with the stated goal of encouraging short internodal spacing and bushier growth. That spectrum suits the early and middle stages of a grow, when height control and dense branching are priorities.
The bulb uses high-quality quartz glass and has a stated efficiency of 100 lumens per watt. Quartz glass is part of the stated build, and the efficiency figure helps compare output per watt with smaller lamps.
This is a high-demand lamp. The fixture must be rated for 1000 watts, and the grow space must be able to handle the heat and electrical load of that system.
Planning the room matters as much as choosing the bulb. Ventilation, clearance from plants and reliable power all need to be in place before a lamp of this size is switched on.
Startup takes 2 to 3 minutes to reach full brightness. Judge the light only after that warm-up period, since the lamp will look dimmer at first.
After shutoff, wait at least 5 minutes before striking the lamp again. Rapid restarts can strain the lamp, so build that pause into any daily schedule.
Vegelumax MH 600W Metal Halide Single Ended: Best for high-lumen vegetative lighting
- 600 watts
- 6000K
- 55,000 lumens
- E39 base
- Electronic and magnetic ballast compatibility stated
This single-ended lamp fits growers who need high output from a 600-watt bulb. Its 6000K color, 55,000-lumen output and E39 base make it a strong option for a larger vegetative space.
Pros
- 55,000 lumens
- E39 base
- 12,000-hour rated life
Cons
- Large 11.22 in diameter
- Needs 2 to 3 minutes to reach full brightness
Vegelumax MH 600W Metal Halide Single Ended suits growers who want high output from a 600-watt E39 lamp. It produces 55,000 lumens at 6000K and uses enhanced blue and violet spectrums.
The bulb is described as compatible with electronic and magnetic ballasts. That gives it a wider stated ballast range than several products here, but you still need to confirm the fixture's wattage, socket and electrical requirements.
Its 6000K color leans cool, which fits vegetative growth better than flowering. Growers who want a warmer spectrum for late growth may prefer a 4000K or 3000K option instead.
Its large 11.22 in diameter matters during setup. Measure the reflector and surrounding clearance before installation, especially in a compact grow tent.
A large bulb also needs care when it is handled and stored. Keep it in its packaging until use, and avoid touching the glass with bare hands during fitting.
The rated life is 12,000 hours, and the bulb is designed to maintain more than 90% of its initial lumen output after 5,000 hours. That maintenance figure is useful for deciding when output may start to fade.
Allow 2 to 3 minutes for full brightness and at least 5 minutes before restarting after shutoff. Those pauses should be part of the daily routine, not treated as optional.
GRUOTVSZAK CMH 315W 3000K 625umol / 4200K: Best for warm full-spectrum flowering light
- 2-pack
- 315 watts
- 3000K
- 625 μmol/s output
- PGZX18 base
- 20,000-hour operating life
This 2-pack is aimed at indoor flowering setups that favor a warmer 3000K ceramic metal halide spectrum. The stated 625 μmol/s output and PGZX18 base make fixture matching essential.
Pros
- 2-pack
- 625 μmol/s output
- 20,000-hour operating life
Cons
- The specs also reference 4200K and 3100K
- Requires a suitable PGZX18 fixture
GRUOTVSZAK CMH 315W 3000K is the best ceramic metal halide bulb here for a warmer flowering-focused spectrum. The 2-pack uses a PGZX18 base and states a 625 μmol/s output.
The product information describes a full-spectrum lamp with suitable UVA output, more blue light than HPS and strong red output per watt. The 3000K color is warmer than the 4000K PROTOPIA bulb, so it may appeal to growers planning around flowering light.
That warmer tone can make the room feel more natural during evening checks. It also changes how plant colors appear, so judge foliage under the lamp itself rather than under room lighting.
Compatibility needs careful attention. The bulb is described as fitting suitable high- or low-frequency fixtures, with low frequency recommended.
Confirm the PGZX18 socket and fixture frequency before installation. A PGZX18 base is different from the E26 base used by the PROTOPIA 315W model.
The stated operating life is more than 20,000 hours, with 90% output maintenance for 10,000 hours. That longer life can reduce how often a grower needs to plan a bulb change.
Warm-up takes about 5 minutes, and the bulb needs at least 7 minutes to cool before use again. Build both periods into the schedule so the lamp is not judged or restarted too soon.
Sunlite MP70/U/MED/PS 03641-SU 70-watt Protected Metal Halide: Best for low-wattage replacements
- 70 watts
- 4000K
- 5,600 lumens
- E26 medium base
- M98/O ballast code
This protected 70-watt bulb suits smaller fixtures and replacement jobs where the E26 base and M98/O ballast match. Its 5,600-lumen output is the lowest in this roundup.
Pros
- Lowest wattage here
- Protected design
- 15,000-hour average lamp life
Cons
- Lower output than the other picks
- Not a ceramic metal halide bulb
Sunlite MP70/U/MED/PS 03641-SU is the best low-wattage replacement in this roundup. It uses 70 watts, an E26 medium base and an M98/O ballast code, with 4000K color and 5,600 lumens.
This protected pulse-start bulb is made for HID uses such as street lights, parking lots, perimeter lighting and commercial interiors. It is not a ceramic metal halide grow bulb, but it belongs in this comparison because some buyers search for a lower-wattage metal halide replacement.
Its lower output suits smaller fixtures and general lighting jobs. For indoor plants, it would work best over a small area or as a supplement rather than as the main light for a large canopy.
The ED17 bulb measures 2.1 in wide and 5.3 in tall. Those dimensions can help when replacing a bulb in a tight fixture.
Checking the measurements before ordering can prevent a poor fit. A bulb that is too tall or wide for the enclosure will be difficult to install safely.
Choose it when the M98/O ballast and 70-watt rating match. Its stated average lifespan is 15,000 hours, which is a long planning figure for a replacement lamp.
Its output is much lower than the grow-focused bulbs, so it is not the best choice for a large indoor plant canopy. Pick it for fit and existing hardware first, not for maximum plant brightness.
Vegelumax MH 400W Metal Halide HID Grow: Best for 400-watt vegetative setups
- 400 watts
- 6000K
- 36,000 lumens
- E39 base
- Electronic and magnetic ballast compatibility stated
This 400-watt bulb gives growers a middle option between 315W CMH lamps and larger 600W or 1000W metal halide lamps. Its E39 base and 6000K spectrum suit vegetative growth when the fixture matches.
Pros
- 36,000 lumens
- E39 base
- Electronic and magnetic ballast compatibility stated
Cons
- 5,000-hour operating life
- Needs 3 to 5 minutes to reach full brightness
Vegelumax MH 400W Metal Halide HID Grow gives growers a middle step between 315W CMH and 600W metal halide systems. It uses an E39 base, produces 36,000 lumens and has a 6000K color temperature.
The bulb's enhanced blue and violet spectrum is aimed at vegetative growth. That makes it a fit for growers who want stronger growth-stage lighting without moving to a 600W lamp.
It is described as compatible with electronic and magnetic ballasts, but the fixture still needs to support 400 watts and the E39 cap. Ballast type alone does not settle the match, since wattage and socket must line up too.
The stated operating life is 5,000 hours, which is shorter than the 12,000-hour Vegelumax 600W lamp and the 15,000-hour PROTOPIA 315W CMH bulb. That trade-off may matter if you want to reduce replacement frequency.
A shorter life means the cost of ownership should be weighed against the output. Growers running long daily schedules may reach that point sooner than those on shorter cycles.
Allow 3 to 5 minutes for full brightness. Wait at least 5 minutes after shutoff before striking it again.
Those timing notes matter for daily care. Planning the switch-on and switch-off routine around them helps the lamp run as intended.
How do ballast compatibility and bulb bases affect your choice?
Ballast compatibility should be checked before spectrum or lumen output. An M58 fixture is not the same as an M90/O, M98/O or M102 fixture, and an E39 mogul base is not the same as an E26 medium base.
Start by recording the ballast code printed on the fixture or ballast. Then match the bulb's ANSI code, wattage and socket.
If any one of those details differs, pause before installation.
For a broader comparison of traditional metal halide options, see our guide to the best metal halide light bulbs. It can help when a ceramic lamp is not the right match for your existing system.
A product can have the right wattage and still be wrong for your fixture. The 100-watt Bluex Bulbs model uses an E26 base and M90/O ballast code, while the 70-watt Sunlite model uses an M98/O code.
Those are not interchangeable details.
Which wattage and spectrum fit an indoor grow?
A 315W ceramic metal halide bulb is the most balanced starting point here. It sits between small replacement bulbs and high-output lamps, with the PROTOPIA 315W 4000K model as the clearest general-purpose pick.
The PROTOPIA model uses an E26 base and a color rendering index of 98, which helps with reading plant color. The GRUOTVSZAK 315W 3000K pair uses a PGZX18 base, so the two 315W options are not interchangeable in the same fixture.
Choose 600W or 1000W only when your fixture and growing area are built for that load. The Vegelumax 600W lamp produces 55,000 lumens, while the PROTOPIA 1000W lamp is intended for a large vegetative footprint.
Higher wattage also brings more heat and larger bulbs to manage. The Vegelumax 600W model is 11.22 in in diameter, so reflector size and ceiling height need a careful check.
For spectrum, 3000K is warmer, 4000K is more balanced and 6000K is cooler with enhanced blue and violet light in the grow-focused models here. A warmer lamp suits flowering, while a cooler lamp suits vegetative growth.
Spectrum alone does not overcome a ballast mismatch. An M58, M90/O, M98/O or M102 code must be matched before color temperature is considered.
Consider operating life alongside wattage too. The lamps here range from 5,000 hours for the Vegelumax 400W model to more than 20,000 hours for the GRUOTVSZAK 315W pair.
A longer-lived bulb may need fewer changes during a long grow cycle. That can matter as much as peak output for a steady routine.
Fixture height is another way to fine-tune the result. Raising the fixture spreads light wider, while lowering it concentrates light on a smaller canopy.
Our guide to the best ceramic metal halide grow light covers complete fixture systems when you need more than a replacement bulb.
How should you install and care for a ceramic metal halide bulb?
Install the bulb only in a fixture with the correct ballast, socket and wattage rating. Read the labels on the fixture and ballast before you order, since a small code difference can make a bulb unsafe to use.
Let the lamp reach full brightness before judging its output. Several products state warm-up times of 2 to 5 minutes, with the GRUOTVSZAK 315W model at about 5 minutes and the Vegelumax 400W model at 3 to 5 minutes.
Avoid rapid restarts. The PROTOPIA 1000W, Vegelumax 400W and Vegelumax 600W lamps all specify a waiting period after shutoff, while the GRUOTVSZAK 315W model states at least 7 minutes of cool-down time.
Build that pause into the daily schedule instead of switching the lamp straight back on. The pause protects the lamp and gives it time to cool properly.
Keep the bulb and fixture clean, following the fixture instructions, and leave enough clearance around high-wattage lamps. Dust and buildup can reduce light output and airflow.
Larger bulbs such as the Vegelumax 600W model need extra attention to reflector size and surrounding space. Its 11.22 in diameter may not suit a small tent or short reflector.
Handle bulbs with care during fitting and cleaning. Clean glass helps the lamp give a clearer, more even light.
Replace a bulb when its operating life or output no longer fits your schedule. A stated lamp life is a planning figure, not a promise that every bulb will look identical throughout that period.
Which ceramic metal halide bulb should you choose?
The best ceramic metal halide bulb for most indoor growers is the PROTOPIA CMH 315W 4000K, especially with a standard 315W CMH fixture and a need for balanced spectrum.
Its E26 base, 4000K daylight white light and color rendering index of 98 make it a strong all-around choice. It suits one lamp for vegetative and flowering phases without extra fixture planning.
Pick Bluex Bulbs if your system uses an M58 E39 fixture and you want a 3-pack. The 250-watt bulbs give 21,000 lumens at 4000K, between the smaller 100-watt models and the larger grow lamps.
Choose the GRUOTVSZAK 315W 3000K 2-pack for warmer full-spectrum light and the Vegelumax 600W for a larger high-output setup. The GRUOTVSZAK pair uses a PGZX18 base, so confirm that socket before ordering.
For a 6000K vegetative lamp, compare the PROTOPIA 1000W, Vegelumax 600W and Vegelumax 400W by fixture capacity and space size. The 1000W model suits the largest footprint, while the 400W model is the smaller step up from 315W.
Check operating life as well as output. The Vegelumax 400W model is rated at 5,000 hours, while the PROTOPIA 315W model is rated at 15,000 hours.
To compare complete systems rather than replacement bulbs, see the best metal halide grow lights. That is the better route when your ballast or socket does not match any bulb here.
For LED alternatives, see the best grow light bulb and the best LED grow light replacement bulbs. Match the choice to your fixture first, then to spectrum and wattage.
Our top 3 picks at a glance
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1
-
2
Best for 100-watt medium-base setups
Bluex Bulbs 3 Pack MP100/U/MED 100 Watt
9.6/10 our score
See it on Amazon -
3
Best for balanced indoor growth
PROTOPIA CMH 315W 4000K Grow Light Bulb
9.3/10 our score
See it on Amazon
Frequently asked questions
What is the best ceramic metal halide bulb wattage?
The best wattage depends on your fixture and grow area. A 315W CMH bulb is a balanced choice for many indoor setups, while 600W and 1000W metal halide lamps suit larger spaces.
Always match the bulb wattage, base and ballast before installation.
Are ceramic metal halide bulbs compatible with any ballast?
No. Ballast compatibility depends on the lamp type, wattage, base and electrical specifications.
The Bluex Bulbs 250W model uses an M58 ballast code, while the PROTOPIA 315W model is intended for standard 315W CMH fixtures.
Confirm the exact match first.
What color temperature is best for ceramic metal halide grow bulbs?
A 4000K ceramic metal halide bulb is a balanced choice for general indoor growth. A 3000K bulb gives a warmer spectrum for flowering-focused setups, while 6000K metal halide lamps emphasize blue and violet light for vegetative growth.
How long do ceramic metal halide bulbs take to warm up?
Warm-up time varies by bulb. The GRUOTVSZAK 315W model states about 5 minutes, while the Vegelumax 400W model states 3 to 5 minutes.
Some high-wattage lamps also need a cool-down period before they can be restarted.
