My experience with heat pads for localized temperature control in a cool room.

[GL3NE]

I posted a question a few months ago asking about heat pads, and the general attitude of the community seems to be "heat the whole room," which did not pertain to my circumstances, as I live in an apartment without a dedicated animal room. So I decided to try something different.

Although I found some promising thermostat/heat pad/automatic digital climate control products with temperature and humidity probes, I did not trust the system to accurately and safely maintain temperature for several different size enclosures sharing the same space. Therefore, I opted for a simpler, albeit more archaic approach.

I purchased some heat pads on Amazon which have a physical thermostat knob. I purchased one small version to test it out. The heat pad arrived rolled up. I decided to tape it up to the back wall of the shelf and place a terrarium two inches or so away from it and check the temperature via digital thermometer which was mounted inside. Over the course of a few days, I made adjustments to the heat pad temperature and distance from the heat pad until it reach an ideal temperature, and it ended up being the heat pad turned up all the way, with the terrarium placed about 1/2" away. This created a perfect heat gradient of about 84 degrees on the warm end, with the cool end being in the mid to low 70's.

I purchased more heat pads of the same type which were 18.5" x 8.5". The big heat pads draw around 20 watts, while the small one draws about 8. For comparison, my phone charger draws around 10 watts from the wall. All heat pads are plugged into a surge protector which is mounted to the shelf. I mounted the heat pads to the back of the shelf with duct tape and tested their temperatures over the course of a day, making small adjustments every few hours. I then placed terrariums (containing spiders) of various sizes several inches away from the heat pad, slowly moving them close over the course of a few hours and with regular checks of the temperatures. Here are my findings:

All of the spiders which I have (A. Avicularia, A. Minatrix, P. Metallica, P. Murinus, B. Emilia, A. Geniculata) migrate to the end of the container with the heat pad. In fact, none of them seem to even go to the cool end of their enclosures much anymore. My A. Geniculata literally began sitting on the wall which was closest to the heat pad, while in the past it would normally just sit out in the open. She also began digging out underneath her shelter on the other end of the container, which I thought was due to the enclosure being too warm, but she still occasionally comes out and sits next to the heated wall. The P. Murinus extended its web to the end of the container closest to the heat pad, and now spends most of its time on that end of the container. The only bug which didn't seem to care are the assassin bugs (P. Biguttatus) - the warm side of the enclosure is about 85 degrees and their behavior hasn't changed much since introducing the heating element.

I am very happy with the heat pads so far, and have been using them for about two months ago. YMMV.

 

[viper69]

And the heat pad models were??

 

[Malum Argenteum]

All of the spiders which I have (A. Avicularia, A. Minatrix, P. Metallica, P. Murinus, B. Emilia, A. Geniculata) migrate to the end of the container with the heat pad. In fact, none of them seem to even go to the cool end of their enclosures much anymore. My A. Geniculata literally began sitting on the wall which was closest to the heat pad, while in the past it would normally just sit out in the open. She also began digging out underneath her shelter on the other end of the container, which I thought was due to the enclosure being too warm, but she still occasionally comes out and sits next to the heated wall. The P. Murinus extended its web to the end of the container closest to the heat pad, and now spends most of its time on that end of the container.

I'm not trying to belittle the info you've shared here -- which is quite interesting and useful for further inquiries into T temp preferences -- but I've learned to judge temp needs by watching animal behavior, and this behavior indicates that raising the overall temp may be a goal worth pursuing. An animal that always hangs on the hot spot is an animal that is being forced to live in one spot for one reason, which is not an ideal husbandry situation.

Again, you've provided useful info but I'm afraid that some readers may miss some implications if they're not pointed out.

 

[GL3NE]

I'm not trying to belittle the info you've shared here -- which is quite interesting and useful for further inquiries into T temp preferences -- but I've learned to judge temp needs by watching animal behavior, and this behavior indicates that raising the overall temp may be a goal worth pursuing. An animal that always hangs on the hot spot is an animal that is being forced to live in one spot for one reason, which is not an ideal husbandry situation.

Again, you've provided useful info but I'm afraid that some readers may miss some implications if they're not pointed out.

I agree with you here. I have kept tarantulas for a very long time and recently revisited the hobby. I know that many people keep spiders at room temperatures (70-75 degrees), and I did as well for a very long time. However it is imperative to at least provide a heat gradient across the enclosure so that the spider can regulate its body temperature, and I was just noting that the spiders heavily favor the very warm end of the enclosure. Heating several enclosures of different sizes is difficult to do safely with heating elements as slight variations of ambient temperature or air flow in the room can very quickly affect the internal temperatures, particularly of the smaller containers. The Geniculata (about 5.5") changes up its distance from the heat source quite a bit. As of this writing, the Usambara (2") is on the opposite end of its container, but spends more time on the warm end during the day.

The rear wall of the assassin bugs' enclosure which faces the heat mat has reached around 87 degrees overnight while the apartment's thermostat was set to its lowest. However, the end of the container (large kritter keeper) which faces outward from the shelf, on the opposite side of the heated end, is usually around 74 degrees. The addition of the heat mat did not affect the day-to-day behavior of the assassin bugs (as far as I have seen) however the shelf is shared with a Crested Gecko which has benefited from the additional warmth.

It isn't easy to provide localized heating - I am in Florida and keep the A/C running continuously in the summer time which makes the room very cold. We set the thermostat to 69-70 degrees at night, and increase to 72-73 during the day. This setup so far had proven to be an excellent alternative to a heated room which I am not able to provide. I raised the Geniculata from a 1/2" spiderling and noticed a change in its behavior since I've added the heating element. However, it's container is currently utilizing a small heating pad - the large one for the entire shelf area just arrived today, so I will be setting it up tomorrow. This should provide a little warmth for the entire enclosure which the spider seems to prefer.

Also, another note: Enclosures dry out MUCH more quickly, especially kritter keepers. None of my spiders are in glass enclosures, all acrylic, and none of the heat pads are directly adhered to containers.

 

[GL3NE]

And the heat pad models were??

I wasn't sure if this was allowed, but here is one I recently purchased:

Simple Deluxe Reptile Heat Pad 8W/16W/24W with Thermostat Temperature Adjustable Under Tank Heater Terrarium Warmer Heating Mat for Turtle/Snake/Lizard/Frog/Spider/Plant Box https://www.amazon.com/dp/B08PYV79C...abc_RDAEQGS3ZNN3KE9R2ZEP?_encoding=UTF8&psc=1

There are many just like this. As far as I can tell, they are all the same thing. Mine are at around 90% power. I recommend spending time adjusting the temperatures and monitoring with digital thermometers (which can also be found on Amazon for very cheap).

 

[Dorifto]

If you keep running the AC all day long, keep an eye on the humidity, I know that you live in florida, but don't know if your ACs humidifies or not, if not heating that air will decreae even more the RH, but giving a bit of moisture to the substrate should prevent any issue.

Yea the heat mat/pad topic it's treated like a taboo, by ignorance or bad information. Folowing some simple rules they are very useful and safe in certain circunstances.

Also you are doing right giving them a temp gradient, Igradient too, imho it's a must when using heat mats. When I used them in the past, my Ts used to move from one spot to the other depending on their needs. The only time I was more vigilant was during premolt/molts, keeping an eye on the moisture, since my old house was pretty cold and dry, and noticed that the heat pad used to dry things way faster during the winter.

 

[GL3NE]

If you keep running the AC all day long, keep an eye on the humidity, I know that you live in florida, but don't know if your ACs humidifies or not, if not heating that air will decreae even more the RH, but giving a bit of moisture to the substrate should prevent any issue.

Yea the heat mat/pad topic it's treated like a taboo, by ignorance or bad information. Folowing some simple rules they are very useful and safe in certain circunstances.

Also you are doing right giving them a temp gradient, Igradient too, imho it's a must when using heat mats. When I used them in the past, my Ts used to move from one spot to the other depending on their needs. The only time I was more vigilant was during premolt/molts, keeping an eye on the moisture, since my old house was pretty cold and dry, and noticed that the heat pad used to dry things way faster during the winter.

Yes, things get really dry pretty quick, but I keep a close eye on the containers and mist or pour distilled water into the substrate if it gets too dry. I notice this issue much more in kritter keepers more so than other makeshift acrylic containers, as kritter keepers allow for much more ventilation.

 

[Albireo Wulfbooper]

I also use this technique at the transitional times of the year - after the heat is turned off in the spring and before it's turned on again in the autumn.

 

[Matt Man]

if your house gets cold a small pad placed near the top and away from the Ts hide can be used. Have it above ground and away from the hide. Lots of folks don't do it and warn against it, but folks in Europe have been doing for years with little issue if placed correct and having the heat controlled / monitored