>>If you really must use an aquarium, I would go no smaller than about 50 gallons. I kept my pair of IJs in 29 gallons for the first few years, and by the time they were near adulthood they were to cramped. In my opinion, there are many much better options than an aquarium. Feel free to contact me if you would to discuss some options or post some questions here. Take care!
I agree...Great rule of thumb for snake caging: The miminum cage lenth should be no less than half the lenth of the snake. IJ max out a 4-6ft as adults. As such your tank needs a minimum 2-3ft lenth. But of course the more room you can afford the better. A 50 gal would be ideal.
A side note, you will need to monitor your humidty with an open-top aquarium depending on the average air humidity were you live. Just keep that in mind
Hope this helps,
Darci
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Takes all kinds to make a World...