Reptile & Amphibian Forums

do you have to put the heat along the back of the rack or can you put the heat (say flexwatt, heat tape, etc) on the actual shelves and place the tub directly on top of it?

I've always wondered, how much of the tubs actually gets heated when the heat is on the back of the rack?

Thanks!
-----
Check Out My Albums

1.0 Ball Python
"Aragorn"

1.0 Kenyan Sand Boa
"Gimli"

0.1 Australian Cattle Dog/Pointer
"Kira"

Just as the long debated "What's the best substrate" question, I don't think there IS a correct answer to this question. There are many keepers/breeders who use backheat with no problems and there is at least an equal amount (if not more) that use belly heat.
I've used both. I started with belly heat years ago and then when I started designing racks and found that back heat would be easier/cheaper/more efficient to install, I gave it a try. I haven't thought about belly heat since
There are definitely pros and cons. The main con to back heat is that it takes more power to get the inside of your tub warm (to the same temp that belly heat would do in a lot less power) because it usually has to go through the tub, and then into the tub a few inches (having a back wall at 90 degrees if that's your hot temp, does no good if the snake can't actually ever be at 90 degrees).
The main pro that I've seen with back heat is that it provides an incredible gradient. With backheat, I'd get my desired temp over the heat tape and 6" away, I'd be close to room temperature so the snake had the choice of being hot or cold with very little in between (unless they lay 1/2 on and 1/2 off then they get a mixture HAHAHA). With the back heat (we'll say using a 32-quart tub), I'll start my gradient at 92 right on the back wall. About 4" in I'll be 90 degrees (my desired temp), then it has a slow rolloff to the front of the tub. The temp on the inside lip of the tub is usually one degree warmer than room temperature. Stop by at the Indy show sometime and I'll show you what I'm talking about (IR thermometers ROCK!!!).
That said, most of the big breeders out there (probably 7 of the top 10 at least) use Freedom Breeder caging which is belly heat, so it OBVIOUSLY works well. I have just yet to see any evidence (personally, from any customers, or secondhand) that back heat doesn't work.
So if you can answer that question, then you can answer the substrate question, THEN you can handle the question "Which came first, the snake or the egg?"
Take care,
Jason @ Jason's Jungle

My fault, I made an error in that post...

I said: The main pro that I've seen with back heat is that it provides an incredible gradient. With BACK HEAT, I'd get my desired temp over the heat tape and 6" away, I'd be close to room temperature so the snake had the choice of being hot or cold with very little in between (unless they lay 1/2 on and 1/2 off then they get a mixture HAHAHA).

It should have said: The main pro that I've seen with back heat is that it provides an incredible gradient. With BELLY HEAT, I'd get my desired temp over the heat tape and 6" away, I'd be close to room temperature so the snake had the choice of being hot or cold with very little in between (unless they lay 1/2 on and 1/2 off then they get a mixture HAHAHA).

Sorry about that,
Jason @ Jason's Jungle

Hi Jason,

That is a very nice gradiant. Don't you think quite a bit of that is due to the 1/2" EPVC/PVCX you use in your racks?

At that thickness acting as an insulative barrier in the back and with the natural conductivity of this material I'd think a similar rack made from 1/4" EPVC or any other 1/2" material would not have the same gradient as your racks.

Which brings up a good point that you elluded to in your post. The effectiveness of backheat vs. belly heat will depend on the design and material of the rack. Obviously the ambient temperature of the room and the species being kept is perhaps the most important consideration. (These last two sentences are targeted to the originator of this thread).

Lastly, the current phylogenetic evidence strongly supports that egg laying is the ancestral condition in snakes

That's a much easier question to answer than the substrate one, IMO

sometimes I amaze myself - I don't know why I didn't just ask you the question to begin with. Especially since if I do go with a rack I plan on buying from you. I was checking out your site and looking at racks built by others and noticed the heat was on the back - guess I just assumed it was belly heat in racks. Pardon my ignorance. LOL.

With your racks, if I were to place it on an outside wall of a room that stays at 72 degrees, do you see a potential problem of maintaining the correct temps for sand boas (and other species with similiar temp requirements)? If so, any way to remedy this?

As always thanks!
Kelly
-----
Check Out My Albums

1.0 Ball Python
"Aragorn"

1.0 Kenyan Sand Boa
"Gimli"

0.1 Australian Cattle Dog/Pointer
"Kira"

Very nice, you just helped me lead into what I was getting ready to post in response to the questions Chris was asking...

One of the biggest keys I've seen with our racks and racks in general is PLACEMENT. An inside wall is very important (IMHO). There are ways around it (for example, using a $6 piece of silver-backed insulation, you can bring the temps up on the hot side by 8 degrees or so) but just out-of-the-box, an inside wall is vital. I'm sure it would work out great in the summer but I know the outside walls in my house (nice 5-year old well-built home at that) are about 6 degrees lower than an inside wall (there is just 6" between the inside of the house and the 20 degree temperatures that await me outside). That's quite a blow when you're trying to retain 90-92 degree temps in your tubs.

Chris, as far as your question, I don't want to mislead people, the backs of my racks are 1/8" material. The rest of the construction is 1/2". I did move from EPVC for my backs to HDPE because I found the HDPE to hold the heat in a little better and is not nearly as frail as the EPVC material (the 1/8" EPVC cracks pretty easy in 20-degree weather). BUT, you have a point, different material and different thicknesses will hold and radiate heat different than other. I don't know the specifics so I can't say what will do better than any other.

In reality, you're absolutely right, moving that material to 1/4" or 1/2" would keep a TON of heat on the inside (therefore why the insulation idea I mentioned above works so well) but that would jump the cost of the racks by at least $25 (again, sheet of 1/2" EPVC runs me about $100) which makes something like the hatchling rack almost out of grasp. I have SERIOUSLY contemplated sucking up about $12/rack and going with the 1/4" material. I may yet, just have to make that 'jump' I've only run into a few customers that had problems and either moving the rack to an inside wall or using the insulation technique worked wonders.

Thanks for the followups,
Jason @ Jason's Jungle

See this little rack made from expanded PVC? It is heated on the back wall only. The plastic material insulates such that the air heats nicely in the back. In addition, the shelves conduct some of the back wall heat to the boxes (about 1-2 inches into the box). Perfect gradient. The ambient air temp is 69 deg in this room as I snapped the picture. The inside back of the boxes are about 84 deg. This racks houses young brooksi (lavender, flame) and a Sinaloan.

If I were using this rack for boas/pythons in such a cold room, I probably would lay a piece of styrene foam insulation against the front of the rack to insulate even more. Either that or try and heat the room a little to pull it up to at least 73 deg.

Its all about insulation, material and room temperature. PVC racks rock in this regard (not to mention being very light in weight.)

.
-----
Check Out My Albums

1.0 Ball Python
"Aragorn"

1.0 Kenyan Sand Boa
"Gimli"

0.1 Australian Cattle Dog/Pointer
"Kira"

If I overlooked this in previous replies, sorry. But it's an important issue that I discovered the hard way.

Maybe you've seen my hatchling rack, and maybe not. I will link it below as reference.

Not only does material and ambient room temp. affect the use of back vs. bottom heat. So does "HEAT SOURCE".

What I mean is the product and size of that product you are using to heat with. Let's make this simple and just address Flex-watt tape...
You will see in my photos that I used 3" tape down the back. I thought this would work. It didn't. The rack is on an inside wall, has 1/8" melamine sheeting on back and then a piece of 1" styrofoam taped on the back of that. The tubs are Rubbermaid 2220. The problem was that 3" tape is too narrow for this application. Because it gets hotter than 4" or 11" for it's size. Plus, the wide lip on the Rubbermaid's was keeping a 1" airspace in the back. I used my temp gun and took a measurement of the temp on the tape. It was 145 degrees F. That is way too hot for this tape. The manufacturer, according to The Bean Farm, says about 100 is the max for 3". And the hot end of my tubs were only reaching 88-90 max. So in order to keep my tubs hot enough, I had to over heat my tape. Can you "Fire Hazard"?

I should have used 11" tape down the back instead. What I ended up doing though is putting 4" tape under the tubs by routing it down, across, down, across, etc. Now I get a great heat and gradient. I had the 4" already so I used it. I would have rather stuck with back heat and used 11".

Melamine gets cold easily. PVC, from what I can tell has a better insulation value.

Each rack, material, heat source, room, animal, substrate, tub design, tub size all make a difference.

I wanted to get this in here before someone else makes the mistake I did.

Troy
Troy's Hatchling Rack

That is a nice rack, who made it? I am looking for rack systems that are light weight, and built for the Sterilite shoe boxes, sweater boxes and the half size sweater box. Thanks for any info.

.
-----
Check Out My Albums

1.0 Ball Python
"Aragorn"

1.0 Kenyan Sand Boa
"Gimli"

0.1 Australian Cattle Dog/Pointer
"Kira"