I have a 75 gallon aquarium that I am converting into a snake cage. I can leave it as big as it is or maybe divide it in half. I already have a kingsnake and a cornsnake and am interested in some sort of python, maybe something other than a ball.
A Jungle Carpet python will do OK in a 75 gallon aquarium and they are pretty hardy and generally quite docile. Many of the other boas and pythons in the 6 foot range get heavier bodied than this and a 75 gallon might be a bit small. If you can find a small Boa constrictor it would do OK as well, but some populations of boa get larger than others so look around carefully.
Basically any snake that stays under 6 feet and is not too heavy bodied would be a good candidate.
In fact we are thinking about starting a reptile class in the local 4-H and my son is interested in breeding snakes so an easy breeder would be a plus too.
If you are interested in breeding, you might be better off with a pair of smaller snakes that you can house together in the 75. African Housesnakes would be a good starter breeder snake that you could house in a 75 with room to spare. Cornsnakes wouldn't be a bad choice either. If you are interested in Pythons, a pair of Spotted Pythons or Children's Pythons would be good candidates, although the babies can be a bit nippy.
Since you live in Central Texas, a pair of nice Baird's Rats would be my choice. Calm, docile, snakes with an understated beauty that has to be seen in person to be appreciated. The babies are somewhat drab gray, but they blossom into a subtly beautiful snake that is a real pleasure to keep. A pair would be fine in that aquarium.
Also, if any one knows of any shows around Austin Texas that would help too.
There is an expo coming up in Austin in August (see the kingsnake.com events page) but there will probably be another one or two before that in Austin or San Antonio. Watch the events page for listings. The best expo in TX is the ETHS expo in Houston in September.
You might also be interested in checking out the yahoo groups for TX Field Herping (http://groups.yahoo.com/group/FieldHerpTexas/) as several Austin natives post there and they may have info about the Central TX Herp society in Austin. Check a few of these forums (general snakes, Bull/Pine/Gopher, Ratsnakes) and search for postings by someone called shaky. Email him (click on his name in a post) as he used to be involved in the Central TX Herp Soc and he would know how to find out more about it.

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Chris Harrison