FAQ: Heating & Lighting for reptiles

A mat is usually not suitable as a tortoise’s main heating, because tortoises bask in the sun from above and belly heat can even be harmful. They need a basking lamp and UVB, and a mat is used only as an extra measure on a specialist’s advice.

Red-eared sliders are usually recommended water of about 24–28 °C and a warmer basking spot on the platform. Water for hatchlings is usually kept a little warmer, and the temperature is checked with a water thermometer.

A turtle tank needs a submersible aquarium heater with a thermostat whose wattage matches the water volume. Turtles are strong and can break a heater, so it should be covered with a guard or a sturdy model, for example with a plastic casing, chosen.

Turtles push and bite equipment, so an unguarded glass heater can break and a turtle can burn itself on the hot surface. A protective cover, or a heater placed in the filter compartment, reduces this risk.

Yes, a water heater does not replace a basking lamp, because aquatic turtles climb onto the platform to warm up and dry their shells. Without a warm, dry spot the shell can soften or develop fungus, so both a basking lamp and a UVB lamp are needed.

Lamps are mounted high enough above the water, ideally over the platform where there is less splashing. A hot bulb can shatter from water drops, so use hoods or guards and keep the lamp out of the turtle’s reach.

A submersible thermometer or a digital thermometer with its probe in the water, placed away from the heater, is the most convenient. If the water temperature differs a lot from one spot to another, improve circulation with the filter.

In larger terrariums the UVB and basking lamps do not always light the whole space well enough, and bright light encourages the reptile’s activity and appetite. An extra daylight LED lamp also helps live plants grow.

No, LED lamps give off very little heat and are only suitable for lighting. Heating needs a separate source, such as a basking lamp, ceramic heater or mat.

About 12 hours of light suits many reptiles, and day length can be adjusted slightly in summer and winter to mimic natural seasons. What matters most is a steady routine, so lighting is most conveniently controlled by a timer.

A simple mechanical or digital plug-in timer works, and a digital one allows more precise times and several on/off periods. Check that the timer can handle the combined wattage of all connected lamps, and after a power cut make sure the time has not reset.

For many reptiles a simple timer works perfectly well, but some keepers choose controllers that mimic dawn and dusk. A simpler option is to switch on the lighting first and the basking lamp a little later, then turn them off in reverse order in the evening.

Live plants need bright enough daylight, usually a plant-growth or bright white LED lamp. UVB and basking lamps are often not enough for plants, and without light they grow leggy and die back.

Reptiles do not need light at night, and a bright coloured bulb can disrupt their rhythm. If you want to watch the animal at night, use a very dim light briefly rather than as permanent lighting.

In winter the room is cooler, so heaters have to work harder and an extra heater that gives no light may be needed at night. Check that the thermostats can hold the temperature and do not place the terrarium by cold windows or in draughts.

On a hot day the room temperature can push the terrarium past a safe level even with a thermostat, since it can only switch the heating off. Keep the terrarium out of the sun, ventilate the room, lower the lamp wattage if needed and watch the temperature on the cool side.

No, direct sun through glass quickly heats a terrarium to dangerous temperatures, and UVB does not get through the window anyway. It is better to place the terrarium away from the window, where you can control the temperature with heaters.

A short power cut is usually not dangerous for a healthy reptile, especially in a warm room. For longer outages you can cover the terrarium with a blanket so it cools more slowly, and in cold weather use heat packs wrapped in cloth, placed so the reptile can move away from them.

Consumption depends on lamp wattage, running hours and the room temperature, since a thermostat only switches the heater on when needed. Good terrarium insulation, correctly sized lamps and a dimming thermostat all reduce energy use.

Yes, a wooden or PVC terrarium usually insulates better and cools more slowly, so heaters have to work less. Glass terrariums lose heat faster, especially in a cool room, so they sometimes need stronger heating.