substrate heater problem

last night we set up our 20 gallon tank. we bought a 8" x 8" Substrate heater from Exo Terra. we dicided to place the heater underneath on one side and turn it on with no substrate in the tank. we also had the cover on the tank. I know it says not to use this type of heater with out substrate but we have yet to get our BP yet so we wanted to see how warm we could get the tank. more of a test run of sorts. well they say that them type of heaters can burn a snake but it hardly warmed the bottom of the cage at all. it is a 4 watts and we couldnt get the overall temperature in the tank over 70 F andf our room temperature is about 68 - 70 F. so it never even warmed the cage. i dont see how this is going to heat the cage once we do get substrate in the cage. what is our problem? thanks

Just a quick question. The Exo Terra Heat Wave that is 8" x 8" is usually an 8 watt I believe not a 4 watt (if memory serves as we looked at them this weekend at our local pet store). Also just wondering what you are using to read the temps with.

I think Exo Terra does have a website if that might be of additional help to you.


~~Jo~~

If you have a digital thermometer with a probe you can get a good surface temp reading. A temp-gun would be better for that but I know that's likely overkill. If you are using an analog (dial) thermometer they can be notoriously inaccurate.

Quite a while ago we'd used a couple of those type pads - one ZooMEd and one ExoTerra i THINK. If it is the kind with the adhesive backing - don't adhere it - once you need a new tank or the pad fails (one of our pads died rather quickly after managing to crack the bottom of a glass tank) they can be a nightmare to get off. The other one (will have to check brands this evening) is still doing well heating a lizard tank.

Any time you are using a UTH with a tank it's a good idea to prop up the tank a bit so that you avoid creating a heatsink underneath and allow some air exchange.

Also on the temp maintenance - what sort of lid/covering do you have for the tank? Without one or with an all screen one the heat/humidity easily bleed out right through the top. We had to cover the screen lids with contac paper (then cut away the corners to allow air exchange) in order to keep the heat and humidity up where they needed to be. My wife still houses her liasis fuscus in this manner and it positively thrives in there.

the tank is well covered but we are using an analog gauge right no. we are goign to get a digital one tonight. but should the UTH make the glass hot? it was just warm enough that u could tell it was warmer. if u had 1/2 an " of sustrate it diffenetly wouldnt have worked.

ok so we did stick the uth to the tank, but how else would we place it there with keeping a space under trhe tank for the air to excape.

How long was it running before you checked the temp? It's going to take it a while to really heat up the glass.

probably 30 - 45 min it was hooked up. we purchased a larger 10 x 11 but it is 8 watts. gonna see what that one does. didnt place it on the glass incase its no good.

I don't know about that brand, but the ZooMeds w/ the adhesive backings take around 8-12 hrs. to get up to operating temps. I also recently acquired a Fluker premium heat mat. It comes w/ no adhesive. you attach it w/ scotch tape on the bottom or side/back outside the tank( glass only ). It does not get any warmer than 100 degrees F on it's surface, and with 3/4 to 1" of substrate, it does a great job of keeping the temps where they should be.

ok now that i gave the tank some time to heat up things are looking better. when i went to bed last night the temp on the hot side was about 83 - 84 and the cool side was about 75 - 77. right now its been really cool in our area with rain so i will expect once the temp rises in the area my apt will rise and so will the cage. thanks for the help.