
Mega-Ray Mercury Vapor Bulb, 100w
The Mega-Ray Mercury Vapor Bulb, 100w, offers a powerful combination of heat, light, and UVB, perfect for your reptile's needs. Renowned as one of the most dependable mercury vapor bulbs in the US, this product is a top choice for reptile enthusiasts.
With innovative technology and over two decades of extensive research, Mega-Ray has managed to minimize the rapid degradation common in other mercury vapor lamps. While many bulbs lose up to 80% of their effectiveness, the Mega-Ray bulb retains over 70% of its potency throughout its lifespan.
This 100w bulb is a self-ballasted PAR-38 True Frosted Flood Lamp, designed to provide a wide spread of usable UVB across a 30" diameter when placed 20" away from the basking spot.
To ensure optimal performance, replace the Mega-Ray Mercury Vapor Bulb every 18 months.
UV Index Readings:
At 12" from lamp — UVI 9.0
At 14" from lamp — UVI 6.0
At 18" from lamp — UVI 3.5
At 24" from lamp — UVI 1.0 - 2.0
Measurements are taken from the lamp face to the basking area or reptile for best UVB and heat delivery.
Usage Guidelines:
Pair this bulb with a wire lamp fixture to avoid overheating issues.
Due to its intense UVB output, this bulb is ideal for spacious enclosures (minimum 24" height) and high-UVB-demanding species like bearded dragons, uromastyx, and chuckwallas. Be sure to understand your reptile’s specific UVB needs and adjust the bulb-to-basking distance as needed.
You might need an extra halogen heat source or UVB lamp to achieve the right temperature or UVB gradient for your pet. Always monitor the basking spot temperature closely and adjust the fixture height to maintain a safe heat range. Double-check basking area temperatures to prevent any risk of burns!
For optimal results, pair this bulb with a Solarmeter 6.5 to ensure your reptile receives the correct UVB levels, available at ReptileSupply.com.

