HCA: Hermit Crab Association

I have two heating pads for my tank but the tank still remains cold. I started with one and stuck it to the side and they only stayed near it because it wasn't enough for the whole tank so I bought another one and put it on the back instead but i have a Styrofoam backing and not even that was warming up and the whole tank was cold. Then I stuck it to the other side but again it did nothing. I don't want to buy a lamp because I have aluminum foil on the lid to keep humidity up and I spent a lot on the heating pads.
I don't have a rheostat for the heating pads but I bought one and its on the way. I have a 40 gallon exo terra tank and zoo med heating pads.

I just typed a response and was booted and had to log back in and lost it. GRRRRRRR.

A few questions:
What size are the heaters you purchased?
What are the temperatures in the room and inside the tank?
What type of lid do you have?
What type of styrofoam are you using to Insulate?

I am thinking your heating pads are 8" X 12" for a 30-40 gallon tank. Depending on the dimensions of your tank breeder or long you could probably add one or two more heaters on the back, and possibly and additional one on the side. That's a total of 4 or 5 heaters, "IF" they are the 8 X 12 Zoo Meds. This is of course all guessing on my part without any information.

Generally in order to properly heat a crab tank you need a heater that will cover the entire back of the tank from the top of the substrate to where the glass meets the black strip at the top also from one side to the other. The sizes on the heater packaging are for reptiles in those size tanks not for hermit crab tanks. Reptiles need a warm spot to lay, they can deal with a wider range of temperature changes so they only need a "spot" to stay warm. Hermit crabs need a more stable temperature in the entire tank so they need a much larger heat source.

Zoo Meds Heaters only claim to be able to raise the temperature 2-8 degrees depending on conditions in their FAQ's section.
https://zoomed.com/reptitherm-under-tank-heater-u-t-h/

Here are two of our set ups that may give you some ideas how to raise your temperature. The room temperature is currently 72.

I just resurrected an old 10 gallon tank (20L X 10W X 13T) we used to use. There is a glass lid with a towel doubled up on top. It has a Zoo Meds 50-60 gallon (18 X8) heating pad on the back. It's been plugged in and running for about 5 hours now. It's reading 77 degrees. No insulation other than the towel.

Our 75 Gallon (48L X 18W X 23T) has two Ultratherms one covers the back of the tank (11 X 48) the other is on one side (11 X 17). Both the back and side with the heaters are insulated with 5/8" thick Polly Pro Insulation Board. One side is a glass lid, the other side is Plexiglass with a 6" hole for a UVB light to sit in. There is also a thermostat set to 86 on the rear heating pad. The current temperature is 85.

I am a firm believer that if you live in an area that gets temperatures below freezing for more than a few days a year you can't have enough heating. I would sooner be able to have a heater and not use it than to need one and not have it.

I pulled this from the general hermit crab care sheet section.
" Under-Tank Heater (UTH)

These are the most popular option for warming crabitats. They are sold for reptiles for use underneath the tank, but in hermit crab enclosures the UTH should only be used on the side or back of the tank. Because of the need of thick substrate in crabitats, UTHs are not effective when used on the bottom and can possibly overheat and become a fire risk. Do not pay attention to the recommended tank size on the packaging - buy the largest sized heat mat that you can fit on the back of your tank as many store-bought UTH run too cool to heat a crabitat. Ultratherm brand UTH must be ordered online, but they are known to run the warmest and are capable of being insulated with styrofoam to boost the heat unlike many other brands. If the UTH runs too warm a plug-in lamp dimmer or thermostat can be used to adjust the temperature. Many crabbers prefer to use a pad that ends above the substrate line so that they do not have to worry about substrate drying out quickly. Also, UTH cannot be bent without damaging them. "

Zoo Meds UTH's CAN NOT be insulated.

Motörcrab wrote:I just typed a response and was booted and had to log back in and lost it. GRRRRRRR.

A few questions:
What size are the heaters you purchased?
What are the temperatures in the room and inside the tank?
What type of lid do you have?
What type of styrofoam are you using to Insulate?

I am thinking your heating pads are 8" X 12" for a 30-40 gallon tank. Depending on the dimensions of your tank breeder or long you could probably add one or two more heaters on the back, and possibly and additional one on the side. That's a total of 4 or 5 heaters, "IF" they are the 8 X 12 Zoo Meds. This is of course all guessing on my part without any information.

Generally in order to properly heat a crab tank you need a heater that will cover the entire back of the tank from the top of the substrate to where the glass meets the black strip at the top also from one side to the other. The sizes on the heater packaging are for reptiles in those size tanks not for hermit crab tanks. Reptiles need a warm spot to lay, they can deal with a wider range of temperature changes so they only need a "spot" to stay warm. Hermit crabs need a more stable temperature in the entire tank so they need a much larger heat source.

Zoo Meds Heaters only claim to be able to raise the temperature 2-8 degrees depending on conditions in their FAQ's section.
https://zoomed.com/reptitherm-under-tank-heater-u-t-h/

Here are two of our set ups that may give you some ideas how to raise your temperature. The room temperature is currently 72.

I just resurrected an old 10 gallon tank (20L X 10W X 13T) we used to use. There is a glass lid with a towel doubled up on top. It has a Zoo Meds 50-60 gallon (18 X8) heating pad on the back. It's been plugged in and running for about 5 hours now. It's reading 77 degrees. No insulation other than the towel.

Our 75 Gallon (48L X 18W X 23T) has two Ultratherms one covers the back of the tank (11 X 48) the other is on one side (11 X 17). Both the back and side with the heaters are insulated with 5/8" thick Polly Pro Insulation Board. One side is a glass lid, the other side is Plexiglass with a 6" hole for a UVB light to sit in. There is also a thermostat set to 86 on the rear heating pad. The current temperature is 85.

I am a firm believer that if you live in an area that gets temperatures below freezing for more than a few days a year you can't have enough heating. I would sooner be able to have a heater and not use it than to need one and not have it.

I pulled this from the general hermit crab care sheet section.
" Under-Tank Heater (UTH)

These are the most popular option for warming crabitats. They are sold for reptiles for use underneath the tank, but in hermit crab enclosures the UTH should only be used on the side or back of the tank. Because of the need of thick substrate in crabitats, UTHs are not effective when used on the bottom and can possibly overheat and become a fire risk. Do not pay attention to the recommended tank size on the packaging - buy the largest sized heat mat that you can fit on the back of your tank as many store-bought UTH run too cool to heat a crabitat. Ultratherm brand UTH must be ordered online, but they are known to run the warmest and are capable of being insulated with styrofoam to boost the heat unlike many other brands. If the UTH runs too warm a plug-in lamp dimmer or thermostat can be used to adjust the temperature. Many crabbers prefer to use a pad that ends above the substrate line so that they do not have to worry about substrate drying out quickly. Also, UTH cannot be bent without damaging them. "

Zoo Meds UTH's CAN NOT be insulated.

One heater is a 30-40 and the other is a 50-60. My room is warmer than the rest of the house so i dont know the temperature and im waiting on a new thermometer for the tank my current one is broken. the lid is a wire one that comes with the tank but i have a sheet of aluminum foil on top to keep humidity up. the styrofoam is what came with the tank as a background i just didnt know if it prevented the tank from heating up. I can definitely get another type of heater. I used to be able to take a heating blanket and drape it over the tank and it would warm it up but i dont want to do that.

The Styrofoam is between the heater and the tank? Or the heater is under the Styrofoam?

curlysister wrote:The Styrofoam is between the heater and the tank? Or the heater is under the Styrofoam?

Its an exo terra tank, so styrofoam is inside the crabitat.


To OP, removing the stryrofoam may help with heating a little, especially since a UTH is behind - from my understanding. The styrofoam would block a lot of the heat, so removing it would be a good choice.

(Also have an exoterra tank with the sytrofoam backing. Looking at it, crabs would have a field day destroying it, so would suggest removing it!)

Sent from my SM-G935F using Tapatalk

Ah, now I get it! Sorry, am not familiar with that type of tank, thanks for clarifying!