you definitely want larger than a 40. minimum is 4 ft by 2 ft by 2 ft
that said bigger is always better. lots of people that have the space use 6 ft by 3 ft by 3 ft. personally, i think that the zen habitats and stuff are realy overpriced for what they are. im building with PVC and one sheet(how much il need for 1 4 by 2 by 2) is about 70$. also dont be fooled by what some say. pine is toxic wich harm your animals respiratory system. if i were going to use wood, or i change my mind, il will be getting sandeply. add up glass and lighting and stuff, maby 150 to 200. also! dont forget a substrate lip! that will make it easyer for sliding doors if you choose that. how are you guys planning to make your doors?
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