Heating Indoor Tortoise Enclosures
- stars & other small, dry area species -
Burmese Star tortoises basking near a heat lamp. Nice lineup! :O)
Always install heating and lighting devices securely and according to the manufacturer's directions. Improperly and unsafely installed tortoise enclosure fixtures have caused many house fires. Keep hot bulbs away from any flammable materials like enclosure covers or nearby curtains. Do install smoke alarms in your tortoise room, garage, cellar, or where ever you keep the enclosures.
It's best to buy UL listed and prewired reptile lighting and heating products. Any do it yourself electrical wiring can be a fire hazard. Unless, you are an electrician and know what you are doing. :O)
Indoor basking areas
You can use mercury vapor bulbs (MVB's), reptile basking bulbs, or regular household bulbs to create indoor basking areas (see lighting). Create a as large as possible basking area that allows the whole tortoise to warm up. Avoid spot heat bulbs that create small, "pinpoint" hot areas on tortoises' backs.
If you are using a long fluorescent tube for UVB, then you'll need a separate reptile bulb for basking heat. Regular household bulbs, CHE's, and radiant heat panels can be used with UVB tubes as well. Always adjust the number and wattage of heat bulbs to fit the size of your enclosure by measuring the warm and cool end temps. Even with a MVB, which provides UVB and heat, you may still need a second heat source to keep the enclosure warm enough.
Well secured light fixtures with ceramic sockets are perfect holders for standard size reptile basking bulbs or regular household light bulbs. Check the wattage rating on the fixture to be sure it takes the wattage of your heat bulb. For example, a typical 5.5" reptile clamp fixture is only rated for a 75W bulb.
Popular heaters used with tortoises include CHE's, reptile radiant heat panels, and "pig blankets." Overhead heat is best; belly heat is not recommended for tortoises.
Ceramic heat emitters (CHE's)
Ceramic infrared heat emitters(CHE's) are great for overnight heating for little tortoises, because they emit no visible light. They can also be used as additional heat sources anytime anywhere. If you use a CHE for daytime basking heat, it needs to be combined with a light emitting bulb, for example, a UVB fluorescent tube.
CHE's and fixtures holding them can get very hot. CHE's can be installed with open wire cage light fixtures, 8"-10" wide reptile brooder light fixtures, or large chicken brooder lamps. Always check that the fixture has a ceramic socket and is rated for your bulb's wattage. Small 5" wide clamp lamps and deep domes are not recommended for CHE's.
Brand new, unused CHE's can emit a slight burning smell when turned on for the first time. I like to preburn mine for a few hours before installing them in tortoise enclosures.
The heated basking / warming up area should be at least as large as the tortoise's shell. CHE's emit heat into a small area, so they work best with little tortoises. CHE's are not recommended for larger tortoises because if placed too close to the tortoise, they an cause spot burns on the shell. Reptile radiant heat panels are a better choice for bigger tortoises.
Radiant heat panels
Reptile radiant heat panels are similar in function to CHE's. They both project infrared heat, but radiant heat panels cover much larger areas. CHE's are screwed in like light bulbs, but radiant heat panels are actually shaped like panels. You attach them to the enclosure ceiling for overhead heat. Choose the panel size based on how large area you want to heat.
Reptile radiant heat panels are excellent for vivariums and heated houses. As with other heating devices, always use them with a thermostat when installed into a closed space.
Reptile radiant heat panels are economical to use. Compare the heating surface area in the above photo between the heaters. That's a 100W CHE and a 80W radiant heat panel. The panel heats a huge area compared to the CHE with the same electricity cost!
Floor heat pads - Yes or no?
Floor heating is a controversial topic among tortoise keepers. Some like to use small undertank heaters (UTH's) or larger "pig blankets" (rigid floor heat mats) when additional night or day heat is required, while others only recommend overhead heat sources. They feel that bottom heat is unnatural for tortoises and can harm them.
All heating devices, especially UTH's, should be used with a thermostat. Never heat more than 1/4 to 1/3 of the floor space. There must always be unheated floor areas available for the tortoise to cool off.
Caution! Be especially careful if using UTH's with hatchlings and youngsters. Stuart McArthur's book Medicine and Surgery of Tortoises and Turtles (2004) includes photos of a hatchling with a fractured plastron and ruptured intestines due to heat from an UTH. The author states that he has seen several such cases. According to Dr McArthur, the digestive tract lies unprotected just above the plastron. Belly heat increases digestive processes and can mess up the fermentation process resulting in a ruptured intestine and death.
Installing undertank heat mats and pig blankets on enclosure walls or ceiling to provide radiant heat is fine. Also much safer for the tortoises.
For safety, it's always best to use a thermostat or a rheostat with ceramic heat emitters, radiant heat panels, heat mats, and other heating devices to control the temperature level.
A rheostat is a dimmer switch that regulates the flow of electricity on a constant rate based on the user setting. Rheostats work best in rooms where the temperature is relatively stable.
A thermostat (t-stat) turns the heater on and off or regulates the electricity as needed based on the enclosure temperature. A non-proportional thermostat works on an on/off mode, and a proportional thermostat constantly adjusts the amount of heat to keep it at the target level. Ideally, each heating device should have its own thermostat.
Many people like thermostats better because they are automatic and will adjust the enclosure temperature if the room temperature goes up and down.
Note: Mercury vapor bulbs (MVB's) cannot be used with dimmers or rheostats, but you can use a timer (automatic on/off) with them.
Using a simple thermostat is straightforward. Plug the heater into the thermostat and the thermostat into the wall outlet. Set the thermostat to the desired temperature level and place the probe to the location in the enclosure where you want to control the heat level.
It's always best to monitor the temperature with a separate thermometer to check if any adjustments are needed. The numbers on the t-stat dial can be a bit off the actual readings. In other words, you may need to adjust the t-stat temperature up or down depending on the true temperature in the enclosure.
I use both Zilla and Hydrofarm thermostats. They are reasonably priced and commonly available.
a.) Zilla & Zoo Med t-stats
The Zilla temperature controller (pic) lets you adjust the heat level to 60-105 °F and the Zoo Med Repti-Temp thermostatto 70-110 °F. Zilla t-stat is a simple on/off thermostat with a manual dial. It's available in 1-plug and 3-plug versions to accommodate different number of heat sources. A-life and Esu Reptile thermostats look exactly like Zilla's.
b.) Hydrofarm t-stat
Another popular thermostat is the Hydrofarm Digital Thermostat For Heat Mats (MTPRTC, pic). This digital t-stat has a control range of 68-108 °F. The updated model has a stainless steel temperature probe that can be submerged in water.
You can plug enclosure lights and heaters into multiple outlet power center timers. Rugged outdoor timers work well, too. This way the tortoise lights will go on and off automatically mornings and evenings. Not a necessary item, but very handy to have. :O)
Caution! Do check daily that the timers, lights, and heaters are working properly. Timers and bulbs can fail unexpectedly. You don't want your tortoises, especially babies, to be too cold for long. Cold and damp can be detrimental to Star tortoises! During very cold weather, tortoises kept outdoors 24/7 in heated houses are most at risk.
You can measure the energy consumption of your reptile bulbs with an electricity usage monitor. Kill A Watt is a popular, inexpensive meter. It's very easy to use. Just plug it in! You may be quite surprised by the electricity consumption of some bulbs and small appliances.
Out of curiosity, I tested some of my UV and heat bulbs. My 100W MVB's actually use 114-120 watts! In comparison, a 20W T-8 UV tube and a 75W reptile basking bulb use 87 watts combined. My 60W CHE's use about 59 watts, and the 75W reptile basking bulbs use about 72 watts.
Thermometers & hygrometers
I use a variety of thermometers and hygrometers. Readings between different types of units can vary, so compare them. Always check the temperatures at both ends of the enclosure to ensure an adequate temperature gradient. Measure the temperature at the substrate level where the tortoise lives.
a.) Dial thermometers
Cheap dial thermometers from pet shops are not very accurate; their readings can be all over the place. High quality hair (haar) hygrometers, which are much more expensive, are are very accurate. I have a German haar thermometer in my incubator in addition to a digital one.
b.) Digital thermometers
I have a bunch of Acu-Rite Home Comfort Monitors. They've become my "default" thermometer-hygrometers for indoor enclosures and egg incubators. They have lasted a lot longer than several reptile brands and models I've used. They are inexpensive and seem to be accurate enough, usually within 1-2 °F of each other. The humidity readings vary a bit more, about 1-5 % or so.
Ideally, use humidity gauges at both ends of the enclosure as well. Or move the devices around to check the temperatures and humidity at various locations. However, hygrometers tend to be slow to respond.
d.) Temp guns
A hand-held temperature gun (temp gun), a digital infrared thermometer, is another useful gadget to have. It allows you to spot check any surface temperature in an instant. Pro Exotics's low-priced temp guns PE1 & PE2 (black PE1 in pic) are a popular choice. I have one of those, too.
e.) HVAC probes
You can also buy a small hand held device that quickly measures both the air temperature and relative humidity (red meter in pic). Heating, ventilating, and air conditioning (HVAC) professionals use them to assess indoor air quality. With these devices, the temperature analysis is quick, but the relative humidity reading takes a bit longer. These probe style digital meters are available from several companies, for example, Amprobe, Extech, and Fluke.
In snow country, it's always good to have an emergency power generator available. Otherwise, disposable heating packs are a great resource to keep at hand for power outages. They are also useful for transporting tortoises in cold weather or keeping incubating eggs warm during a power outage.
These heat packs typically last from 2 to 70+ hours depending on the rating. The less time they give out heat, the cheaper they are. Heat packs are mostly sold as hand, body, and foot warmers for short time use. They are available under several brand names. Heat pads designed for humans may not have the right temperature for reptiles. As always, check the temperature before exposing your tortoise to it.
Among reptile keepers, the UniHeat Shipping Warmers are the most popular. As the name implies, these packs are intended to keep reptiles warm during shipping. They put out heat for 20-72 hours depending on the model.
UniHeat packs are non-toxic and non-flammable. Still, I would wrap the packs in a light towel or layers of paper to prevent tortoises from ripping them open. I keep a bunch of UniHeat warmers (pic) at home, just in case.