How big of a cage do you need for a salamander?

Assuming that you have a tiger salamandar (regular/common salamandar) You need a cage that will be big enough for dirt, A dish of water, plants, bark. Salamandars produce quite a bit of waste so you need to keep in mind that if you want a healthy salamandar then you will have to clean it frequently. There is no exact measurement I can give you, because It's your descision about your cage. I guess you can find a nice medium size and still keep in mind those things I stated.