Perhaps you’ve just started researching for your first leopard gecko, or perhaps you’re onto your third clutch of Asian water monitor eggs in a successful breeding project. Either way, you’ve almost certainly come across heat lamps and the concept of temperature. That’s why today we’re going to talk about what makes the “best” reptile heat lamp.
At this point you know that you can provide a UV lamp to help replicate those all-important UVB rays that animals get from the sun. And of course, your heat lamp replaces the heat from the sun. But that’s not the entire picture.
The sun provides a plethora of light, but depending on your definition of ‘heat’; it might not actually provide any heat at all. If we go by one common term of heat being “the transfer of thermal energy from one place to another via conduction,” the sun provides none to us on earth!
What it does provide is electromagnetic and thermal radiation.
You’ve probably heard the term “infrared”. And this is generally associated with heat. But that’s confusing too, because that’s not wholly correct. It’s actually a name given to certain types of radiation – it can just as easily be classified as a type of light.
The manufacturers don’t make it easy by producing lamps like red “infrared” bulbs, “heat projectors”, “infrared projectors”, and then you can buy an “infrared thermometer” for getting temperatures.
It’s a mess! There’s so many terms that the hobby uses interchangeably without any reason or rhyme, and they make it your job to navigate it all!
So, let’s try to define what we mean. That’s really important before we get confused in our own terminology.
What is Infrared?
We know that the sun emits light (electromagnetic radiation), and that we see colours of the rainbow thanks to light from the sun. Well, infrared can be considered the exact same as colour, in a sense. It’s just a type of light that is invisible to humans, so although we can see “green” light, we can’t see “infrared” light.
If you read “infrared” in this post from now on, I’ll be referring to infrared as if it’s a colour. An invisible colour. If we shine enough green light at your hand, it will warm your hand up. Similarly, enough infrared will also warm your hand up.
If you go outside on a sunny day at around 1pm, about 45% of the light that hits you from the sun will be invisible infrared. That’s a lot! And a portion of this invisible light will warm you up.
- Fun fact: A very significant amount of the “warming effect” we get from the sun is also from visible light (the colours) — not just the infrared!
It also does plenty of other things for the body. It has a healing effect, and helps the body to upregulate genes. Infrared is even used in medicine to help heal wounds – water-filtered halogen lamps have been used for years for this purpose, and now specialised lasers are becoming more commonplace. I’ve seen specialised veterinary lasers be used on everything from snakes to elephants.
It’s this ‘45% of sunlight’ that we want to replicate in captivity. We want that heating effect, sure, but we also want those other benefits like the metabolism-boost, healing effect, and the endorphin release. And choosing the right reptile heat lamp for your situation is important to get this.
Tom’s knowledge box:
The type of infrared that we associate with sun-like heating and it’s healing effects is called Infrared-A. The types of infrared that we generally associate as being unnatural are called infrared-B and infrared-C
Here’s some ideas of radiative output from different sources…
- Sunlight (average): 45% IRA, 32% IRB, 2% IRC.
- Incandescent lamp at 100% power (~2700ºK): 38% IRA, 39% IRB, 12% IRC.
- Heat Projector at 100% power (~1000ºK): 8% IRA, 48% IRB, 44% IRC.
What are the best reptile heat lamps for infrared?
By far the best reptile heat lamps are going to be the ones that replicate this ‘45% of sunlight’. The winners? The classic “basking lamp”! These are incandescent bulbs that can also sometimes come in a formfactor called a “halogen”, and they glow white hot when turned on.
- Fun fact: It’s actually this “white hot” effect that makes it so perfect, it’s a sign that they emit something called Black Body Radiation. The little metal filament inside the bulb gets very hot, around 2400°C (around 4500°F) and starts to glow. The sun is doing the same thing, it’s just much hotter at closer to 5400°C (around 9700°F) on its surface.
Thanks to some pretty lucky science, the peak power of the output of the heat lamp is infrared – and matches fairly closely that 45% we’d get from the sun! What we’ve essentially got is a mini, slightly cooler, sun in our enclosure.
Now, here’s the fun bit: the cooler that filament gets, the less like the sun it becomes!
If we dim down the bulb, the filament gets colder, and the output becomes less and less like the sun. The output ‘shifts’ away from outputting the useful – basking – infrared, and instead outputs more and more of the unnatural – drying – types of infrared.
This has some pretty big implications. It means that if we dim down our lights, we’ve defeated the purpose of trying to provide that ‘45% of sunlight’! We want to dim lights as little as possible.
But what about temperatures?
Choosing the right basking temperature
Although measuring surface temperatures is important for ensuring the safety of our animals, it’s not the best way of determining if a heat lamp is suitable for your animal. And measuring ambient temperatures tells us even less about the bulb! We shouldn’t ignore these things, but there must be another way to approach this, right?
Well, first we have to set aside the thought of temperatures, just for a moment.
When you choose a UV lamp, it should be based on the question “does this lamp provide the adequate levels of safe UVB to my animal when basking?”. A very similar question should be asked when choosing a basking lamp too. You should ask:
“Does this basking lamp provide adequate levels of safe sun-like infrared-A to my animal when basking?”
And not:
“Does this heat bulb get the substrate up to a certain temperature?”
And then you get an idea of the approach we should take when choosing the best reptile heat lamp. That’s all well and good, so how DO we decide if a basking bulb is right? And why does a heat projector not fit into this?
A really safe method of testing your basking lamp is quite primitive but works remarkably well. After the lights have all been on for 2+ hours (undimmed), place your hand on the basking surface. You should be able to hold your hand there for a long time without it feeling too hot.
Then, have your hand raised so it’s hovering at about the height of your animal’s back when basking. Again, with all the lamps on, you should be able to hold your hand there in that position and not get too hot. You should feel the gentle heat from the lights, but you should never get uncomfortable.
It’s honestly amazing how well this works. What you’ve done is shown that even with lights on full power, and after a few hours of exposure, the surface still doesn’t get “too hot”, and your animal wouldn’t cook if they sat under the lights. You’ve proven your basking setup is safe.
And if you’ve felt the gentle warmth on the back of your hand, you’ve also proven that there’s plenty of infrared irradiating the basking area.
Not bad, right?
Now, this only works for a classic incandescent basking light, not for a heat projector or ceramic heater. Remember those ‘unnatural’ (drying) types of infrared I mentioned earlier? They can mislead you a bit when using this ‘hand under the lamp’ method – and it’s those misleading and unnatural types of infrared that heat projectors and ceramic heaters emit!
A heat projector is essentially a heavily dimmed basking light – it’s not useful for basking at all!
But, you can use a heat projector to increase temperatures if your enclosure isn’t warm enough. Just remember to run it on a dimming thermostat, so that it only comes on when your enclosure is too cold. And similar to any other heating device – always make sure it won’t overheat your enclosure if something goes wrong and it is left on at 100% power.
You’ll often find that reptiles can tolerate much cooler temps than you might think. Check out the ReptiFiles care manuals and sheets to find out more about this.
Conclusion
Don’t forget that this is just one piece of the puzzle. You can use a high-quality UVB lamp, and you can install the best reptile heat lamp money can buy for infrared, but the fact is that both of these emit terribly low levels of usable visible light. So you need to also supplement your setup with bright, high-quality light from another source. This can be something like a well-made halide lamp, or an LED with a high colour rendering index.
References:
Holick, M. F (2016) – Biological Effects of Sunlight, Ultraviolet Radiation, Visible Light, Infrared Radiation and Vitamin D for Health. Anticancer Research 36: 1345-1356
Kelber, A., Vorobyev, M. & Osorio, D. (2003) – Animal colour vision – behavioural tests and physiological concepts. Biological Reviews, 78 81–118.
Grace, Michael S. (1997) – The visual system and non-visual photoreception. The Biology Husbandry, and Health Care of Reptiles. Lowell Ackerman, DVM, ed. Vol. I, pp. 325-341.
Tosini et al. (2001) – The circadian system of reptiles: a multioscillatory and multiphotoreceptive system. Physiology & Behavior 72, 461-471.
Sinclair, Sandra (1985) – How Animals See: Other Visions of Our World. Croom Helm, London.
Interview with Roman Muryn C.Eng published in 2019 – Next level heating. Why infrared wavelengths matter. Peregrine Livefoods News, pet industry publication, Peregrine Livefoods Ltd.
Shang-Ru Tsai and Michael R Hamblin (2017) – Biological effects and medical applications of infrared radiation. J Photochem Photobiol B. 2017 May; 170: 197–207.
Liebert A., Kiat H. (2021) – The history of light therapy in hospital physiotherapy and medicine with emphasis on Australia: Evolution into novel areas of practice. Physiother. Theory Pract. 2021;37:389–400
Avci P., Gupta A., Sadasivam M., Vecchio D., Pam Z., Pam N., Hamblin M.R. (2013) – Low-level laser (light) therapy (LLLT) in skin: Stimulating, healing, restoring. Semin. Cutan. Med. Surg. 2013;32:41–52
Kurach et al. (2015) – The Effect of Low-Level Laser Therapy on the Healing of Open Wounds in Dogs. Vet. Surg. 2015;44:988–996.
About the Author:
Thomas Griffiths is an exotic animal husbandry educator and consultant with a specialty in enclosure lighting. He provides professional interactive training courses, personalized husbandry consultations, enclosure design, and independent product testing. His mantra is simple: do what’s best by the animal, and achievable by the keeper.
Website: Tomaskas.co.uk Instagram: @thetomaskas