The Importance of Lamp Reflectors

The correct provision of light and of course energy from light for captive Reptiles and Amphibians is essential.

These animals have developed over vast periods of time in order to take everything that they need to ‘thrive’ from the wild habitat. The sun is the main source of energy, providing for and sustaining all life. The sun projects a natural ‘Full-Spectrum’ of light over all of the terrestrial wavelengths, from UVB to Infrared-B into our atmosphere. It is within this ‘Full-Spectrum’, being natural and balanced, that an animal finds the energy that it needs to thrive. Every part of this Full-spectrum has a use and an interaction within the biology of an animal and therefore must be provided for in captivity in a safe and measured way.

Reptiles, being ectothermic or ‘cold blooded’ are termed as being ‘solar-reliant’. They use Infrared-A and Infrared-B as a source of energy, it is these groups of wavelengths that provide ‘Heat’. This energy then allows them to move, feed and to carry out their essential biological processes. If the level of energy supplied within captivity does not cater for the developed or ‘wild’ needs of the species, the species would be ‘undersupplied for’ and unable to either move or carry out its core biological processes to the same degree as the wild variant. Undersupplied animals are usually lethargic, do not show high levels of wild-like colouration, are less able to process nutrition, can have reduced organ function and as such are more likely to experience avoidable health concerns.

As is well known, animals also use Ultraviolet in both of the terrestrial groups of wavelengths. Ultraviolet B ‘UVB’, when provided in the correct quantity or ‘Index’ will cause a series of changes within the body that will start and maintain the correct production, storage and use of vitamin D3 in the ‘D3 Cycle’. Vitamin D3 is essential to the assimilation, storage and use of ingested full-spectrum minerals, in particular Calcium and Magnesium. It is also used in almost every other biological cycle and function within the body. UVA in a similar way plays an important role within the health and wellbeing of these animals. It allows many species to ‘see’ correctly through activated vision, this activated vision being involved with mate and food selection. It also has uses within other biological cycles, many of which start in the brain.

Reptiles also require a high quantity of light from the visible part of the spectrum, especially those with the pineal organ. In a sense light ‘energises’ their brains through the skull and activates a series of natural biological processes.

‘Light’ and its correct provision is essential. As keepers, we have known for many years just how important the accurate provision of heat and UVB is. We are now starting to become very accurate with our ‘Full-Spectrum+UVB’ lighting systems and recently with the inclusion of dedicated ‘Deep Heat Projectors’ which generate and project true Infrared-A and Infrared-B wavelengths as accurate and usable heat, deep into the dermis, just as is found from natural sunlight.

All technology has limitations; after all, we are trying to replicate one of the most complex energy sources common to our planet: the sun. For example, we know that the small group of wavelengths known as ‘UVB’ are quite weak. They decrease in potency (or ‘Index’), the further that light travels from the lamp. This has led to the invention of stronger UVB lamps that can be sited at a safe distance from the animal, lowering the risk of avoidable diseases from an under-provision of UVB exposure and the subsequent reduction in available vitamin D3. This would lead to mineral stores being overused and the animal would become at risk from developing metabolic bone disease ‘MBD’. The reduction of available D3 would also negatively affect other core biological processes within most of the vital organs.

It is therefore vital that we work within the limitations of the technology that is available to us. We will certainly need to conduct careful thought to the decorative style of our enclosures, ensuring that ‘Wild-Like’ basking is provided for correctly.

The main limitation to most of the lamps that we use is that they emit a large quantity of light entirely in the wrong direction. Think of a linear fluorescent tube lamp. As you can see, these lamps project light out from whole 360 degrees of the glass cylinder. This means that the majority of the light that the lamp is producing is therefore wasted, simply because it is being projected over and around the lamp rather than directed at the animal. Historically, some reptile keepers have lowered lamps down into the animals’ living space or placed them very close to the basking zone in order to increase the quantity of UV available to the animal. This is not a safe practise; lamps can be very bright indeed. Reptiles have developed to live with and to use energy from the sun travelling downwards from above the head. Many reptiles have even have developed hard protruding eye socket bones that act as sunshades so placing a bright light source unnaturally close to, or horizontal to the eye, greatly increases the risk of glare related eye infections such a photo-kera-conjunctivitis. Lamps should always be placed above the animal and at a safe distance where the animal is protected from horizontal glare. So, how much of the total quantity of light produced by a lamp is actually travelling downwards and onto the animal where it is needed most? This depends slightly on the type of lamp used but it is actually very easy to measure with a suitable light meter. On average only around 50% of the total light produced by a lamp is travelling in a useful direction – down to the basking zone.

A specially curved reflector designed for each type of lamp will work with that lamp to ‘capture’ and ‘reflect’ almost all of the light that the tube produces, reflecting it downwards over the basking zone where it is needed most. This in turn increases the quantity of visible light produced or ‘lux’ and ensures that all of the vital Ultraviolet energy is being placed within the basking zone where it can be utilised by the animal.

Typically, a specially curved, highly polished reflector, designed individually for either HO-T5 or T8 lamps provides the very best results when used inside of an enclosure. A highly polished but ‘dimpled’ reflector produces far better results when used over a wire mesh. (approx. 20% available light increase with polished dimples when compared to a polished undimpled reflector sited over a standard wire mesh). Typically, a specially designed reflector will double the quantity of light and UV Index made available over the basking zone.

The following chart shows a number of Reptile lamps with differing percentages of UVB. You will see very quickly how UVB energy decreases as it travels over distance and how a reflector can compensate for this worrying decrease. We should seek to fit a lamp and reflector that supplies the required index of energy for your species at 12-15” (30-40cm) from the lamp to the top of the animal’s head when seated at the zenith of the basking zone. The UV-rich light over this zone should cover the animal at least from nose to vent and be matched with access to equal shade to allow wild-like ‘Self-regulation’. This is called the ‘light and shade’ or ‘Sunbeam’ method.