Hey,
What kind of set up do you have your little Blood in at the moment? For small babies, and juvies, the best cage type, is the ones made by Rubbermaid. They make several small to large plastic containers which can easily be converted into a snake enclosure with a few modifications. Small holes along the periphery of the box will need to be made using a drill gun with a 1/4 inch drill bit, or easier still, is to get a soldering iron from either Radio Shack, or some other supplier. Make at least 5-15 holes along the side of the box, based on the size that you are working with, using either tool.
I use the #2221 and #2223 RubberMaid containers for my set ups and enclosures. They provide the snakes with ample room for either basking if such a hot spot exist, and also, it allows for other cage accoutrements such as 2 hide spots and water bowl. You can find these at either a Walmart, Kmart, or any good hardware store that sells the Rubbermaid brand of plastic containers. I have been able to find these in various places, including the above mentioned carriers.
Hide spots should be controlled very carefully, as the snakes can very easily be burned if hot spots are left unchecked and temperatures are not controlled and monitored carefully too. For heat, I use the "Flexwatt" 3inch and 11inch, heat tapes, for providing heat to my charges set up in a rack system. The heat sources are controlled using a "Helix DBS 1000" thermostat, made by "Helix". These units are without a doubt a most indespensible tool, for any keeper keeping either one or more Bloods or Short-tail, and other snakes or reptiles. Hot spots, should not be left to wander into what ever the heat source is allowed to, but should be controlled and adjusted to reach only a maximum temperature only. A temperature of 85-90 degrees Fahrenheit, should be the most allowed for the hot spot and no more than that. Snakes sometimes will lie atop of heat sources with no controller set up and will end up with severe burns if left to their own devises. So it is important that you get your self some kind of controller in the way of a thermostat immediately for you set up.
Heat mats are fine provided that they are not used inside enclosures with snakes and other reptiles, as these heat sources too, can get quite hot very fast, if left unchecked. Again, a thermostat should be used for such a device.
Temperatures should be set to reach a back ground temperature or ambient temperature of 78-82 degrees Fahrenheit, and not more than that. Humidity should be set for 60-80% by spraying the cage every other day, if using newspaper, and less if you are using some kind of substrate that retains moisture more readily, like cypress mulch or sphagnum moss. The substrates should not be allowed to become saturated or wet as these substrates can easily retain too much moisture if left unchecked too, and could easily lead to skin blistering and other health issues.
If you see the article written by Robbin, of ProExotic, they have a very basic set up for their bloods and short-tails, that works great with new and older established keepers. They use over turned flower pots with a notch or hole cut out for easy access for the snakes to enter and exit. Any good, small plastic container with a hole cut into it, will work too, and will have the same effect; however, they have outlined some find points that work. Read them carefully, and read them over till you start to get the points made. Kara Glaskow, has outlined some other fine points and has written a very fine caresheet available on the "Nerd" web-site". Read that too and you'll start to find your way around the bloods and short-tail issue.
Note: The question regarding the size food to feed your blood was covered by someone else, but just remember, that, the food item fed to your snake, should be one that leaves a small bump or bulge at the thickest part of the snake being fed. Anything larger than that, should be avoided. Usually the thickest part of the snakes body is found toward the middle portion of the body and mid-section.
I hope that this helps some. - Angel
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Discovered and defeated of your prey, You skulked behind the fence, and sneaked away. --Dryden.