Why this product
Most reptile heat questions on owner forums end the same way. Someone asks why their bearded dragon will not bask, someone else asks what bulb to buy, and the third reply tells them to just get a Zoo Med Repti Basking Spot Lamp in the right wattage and stop overthinking it. The bulb is genuinely the default for a reason. The internal silvered reflector creates a tight basking beam rather than the diffuse heat sprawl of a household flood, the wattage range covers everything from a leopard gecko to a Sulcata tortoise night box, and at $7 to $11 per bulb the 6 to 12 month replacement cycle is the cheapest part of running a reptile.
For this review, the analysis draws on Zoo Med’s published bulb specifications, recent Amazon owner long form reviews, reptile keeper forum threads on bulb life and safety, and direct comparison with three other basking bulbs in the same class. Zoo Med did not provide a sample. Where we cite a measurement, the source is the manufacturer or aggregate owner reports.
How we evaluated reptile basking bulbs
We looked at four things. First, beam profile, the basking spot lamp is supposed to focus heat on one spot without warming the cool side of the enclosure into a thermal pancake. Second, wattage availability, the same bulb family should cover small to large enclosures so an owner does not have to switch brands moving from a 20 gallon to a 75 gallon. Third, safety construction, UL listing and a glass envelope rated for the heat output. Fourth, replacement cost and availability over the long term. For our standard reptile setup approach, see our methodology page.
Who should buy
Buy the Repti Basking Spot Lamp if you keep a bearded dragon, blue tongue skink, leopard gecko, crested gecko, or any small to medium diurnal lizard and need a tight beam basking heat source. Buy it if you have a turtle basking dock, the 75W or 100W is the right starting wattage for most red eared slider tanks. Buy it if you are replacing a generic hardware store flood that has been spreading heat instead of focusing it.
Skip the Repti Basking Spot Lamp if you need UVB, this is not a combo bulb. Skip it if you keep nocturnal species in a cool room where you need a 24 hour ceramic heat emitter rather than a daytime cycle bulb. Skip it if you are running a deep dimmer thermostat that pushes the bulb into 50 percent output most of the day, the dimming reduces filament life enough that a ceramic heat emitter on the same dimmer is the better choice.
If you keep a leopard gecko specifically, the Zoo Med ReptiHabitat Leopard Gecko Kit review covers the right enclosure pairing for this bulb at the smaller end of the wattage range.
Beam profile and the cool side problem
The Repti Basking Spot Lamp’s tight reflector is the feature owners come back to. A typical household BR30 flood spreads heat over a wide area, which is fine for a kitchen ceiling but a problem in a 40 gallon reptile enclosure. With a wide flood, the basking spot is barely warmer than the cool side, the reptile cannot thermoregulate properly, and food digestion suffers. The Repti basking bulb concentrates the heat output into a 30 to 40 degree cone, which means the basking surface directly under the dome runs 25 to 40 degrees Fahrenheit hotter than the cool corner of the enclosure. That gradient is the entire point of a basking bulb.
In practice, owners who measure with a temp gun typically see the basking surface at 100 to 110F under a 100W at 8 to 10 inches, with the cool side staying in the high 70s to low 80s in the same room. Those numbers will shift with room temperature and dome height, but the gradient between hot and cool spot stays consistent.
Wattage selection by species and enclosure
The Repti family ships in five wattages and the right pick depends on enclosure volume and target basking temperature. For a 20 gallon leopard gecko, the 50W or 75W lands the warm hide floor in the upper 80s to low 90s. For a 40 gallon bearded dragon juvenile, the 100W is the standard pick. For a 75 gallon adult bearded dragon, the 150W is typical. For a turtle basking dock with the bulb 10 to 14 inches above the dock, the 75W to 100W range is most common. For a Sulcata or Russian tortoise night box in a cold garage, the 250W on a thermostat handles the deeper enclosure volume.
The reason wattage matters more than dome height for many owners is room temperature. A reptile enclosure in a 65F basement needs a hotter bulb than the same enclosure in a 75F living room to hit the same basking spot temperature. Always confirm with a digital probe at the basking surface rather than guessing from a chart.
Bulb life and the replacement cycle
A tungsten filament basking bulb is a consumable. The 2000 hour rated life works out to roughly 6 months on a 12 hour daylight cycle. Owners who run a thermostat with a dimming output stress the filament more during ramp up and ramp down cycles, which can drop life to 4 to 5 months. Owners who run an on off thermostat or no thermostat at all on a stable line voltage typically see 8 to 12 months. The single biggest cause of premature failure is a water droplet hitting the hot glass during misting, which cracks the envelope and ends the bulb instantly. Misting is best done with the lights off and given 10 minutes to settle before the bulb comes back on.
Budget for two to three bulbs per enclosure per year and the math works out to about $20 to $30 annually per basking spot, which is the cheapest line item on most reptile keeping budgets.
Zoo Med Repti Basking Spot Lamp 100W vs. the competition
| Product | Our rating | Beam | Wattages | UL listed | Price | Verdict |
|---|---|---|---|---|---|---|
| Zoo Med Repti Basking Spot Lamp 100W | ★★★★☆ 4.4 | Tight | 50 to 250 | Yes | $9 | Top Pick |
| Fluker's Repta-Sun Basking Bulb | ★★★★☆ 4.3 | Tight | 50 to 150 | Yes | $8 | Runner-up |
| Exo Terra Sun Glo Basking Spot | ★★★★☆ 4.2 | Medium | 25 to 150 | Yes | $11 | Recommended |
| Generic Hardware Store Flood Bulb | ★★★☆☆ 3.4 | Wide | Limited | Not for reptile use | $6 | Skip |
Full specifications
| Wattage options | 50W, 75W, 100W, 150W, 250W |
| Base | Standard E26 medium screw |
| Reflector | Internal silvered tight beam |
| Bulb shape | BR30 style with reptile beam profile |
| Rated voltage | 120V |
| Average rated life | Approximately 2000 hours |
| Recommended dome | 5.5 to 8.5 inch ceramic dome with thermal switch |
| Spectrum | Visible plus infrared, no UVB |
| Safety listing | UL listed for reptile use |
| Made in | China |
Should you buy the Zoo Med Repti Basking Spot Lamp 100W?
The Zoo Med Repti Basking Spot Lamp is the bulb most established bearded dragon and leopard gecko setups quietly run. The tight reflector beam concentrates heat on a single basking spot without sprawling across the cool side, the 100W version puts most 40 gallon enclosures in the right basking range with a standard ceramic dome, and a $7 to $11 price per bulb keeps the 6 month replacement cycle reasonable. Owners who try generic household floods almost always come back to this bulb.
Frequently asked questions
What wattage do I need for a bearded dragon in a 40 gallon tank?+
Most bearded dragon owners run a 100W in a 40 gallon at 8 to 10 inches above the basking platform, which lands the basking surface in the 95 to 110F range. Always set the final wattage with a digital probe thermometer at the basking surface, ambient room temperature changes the right wattage by a step in either direction.
Does this bulb provide UVB?+
No. The Repti Basking Spot Lamp is a heat and visible light bulb only. Diurnal reptiles like bearded dragons, uromastyx, and most diurnal lizards also need a separate UVB tube fixture, typically a Zoo Med ReptiSun 10.0 T5 HO or an Arcadia D3+ T5. Crepuscular species like leopard geckos can be run with a low output UVB or with vitamin D3 supplemented diet plus this basking bulb.
How long does the bulb actually last?+
Rated life is around 2000 hours which is roughly 6 months on a 12 hour daily photoperiod. Owners who run shorter days, who use a dimmer thermostat, or who avoid frequent on off cycling typically push the bulb to 8 to 12 months. The most common cause of early failure is a water droplet hitting the hot glass during a misting session, which cracks the envelope instantly.
What dome should I pair with it?+
A 5.5 to 8.5 inch ceramic socket dome with a built in thermal switch. The Fluker's Repta-Clamp Lamp 5.5 inch is the dome most owners pair with the 100W bulb. Avoid plastic socket domes with this bulb, the heat at the base will deform a plastic socket within months.
Is the 250W version useful for tortoises and large enclosures?+
Yes for outdoor tortoise night boxes, large iguana enclosures, and 75 gallon plus reptile rooms in cold climates. For a typical 40 gallon vivarium the 250W is too hot and will require raising the dome 18 inches or more above the basking platform, at which point a 100W is the safer choice.
📅 Update log
- May 10, 2026Initial review published. Comparison set covers Fluker's Repta-Sun, Exo Terra Sun Glo, and a generic hardware store flood.
