Temperature issues.


Sep 28, 2017
Hello just need a bit of help with heat mats. I no the safest way of using a heat mat is attaching it to the side of the tank.

The question is will it do some damage to my tarantulas if there chilling right on the glass where the heat mat is?. I have polystyrene on the tank with a heat mat behind but the temps aint great. I came back from work today and noticed the temps were around 68f so i freaked out and started using my space heater..but i cant afford to use it. UK weather!!.


Old Timer
Jun 27, 2010
Tarantulas are aware of temperature and will try to move away from a heat source if they become too hot. The problem with heat mats underneath a tank is that a tarantula's natural instinct when trying to avoid heat is to dig down into the ground - which, in that case, actually brings them closer to the heat mat. That's why under-tank mats or heaters should never be used for tarantulas. As long as the mat is on the side of the tank, the tarantula should simply climb down if it gets too hot.

One slightly safer alternative is to double-tank your spiders - particularly those that are in smaller enclosures. You can put the small enclosures inside a larger tank, then attach the heat mat to the side of the larger enclosure, eliminating any chance of direct contact between your spiders and the heated surface while still offering them a warmer environment. Put a good lid on the large outer tank to keep the heat and humidity in and you've created a cozy little microclimate for your pets.

The Grym Reaper

Jul 19, 2016
If you run the heat mat on a thermostat (attach the probe to the mat so that it cuts out when the mat reaches the specified temp) then it's not a problem, I used to use heat mats but I have 40 tarantulas now so it's easier and more efficient to use the space heater.