Is it bad to mix a Tree Frog with a Toad?

Yes! Most of them secret toxins that are poisonous to other species. It is best to cohabitate only the same species. Also, depending on which type of frogs and toads we are talking about, they could require very different environment.

I hope your right man, I spent 20-30 minutes with my toad holding it (even though it was scared to death) I was sad (I feel love towards almost anything) but I found a bucket outside with a crack so he could crawl in and out and I put him there since its day light, well... At least I got my docile green tree frog, wish I could find more. I found him on my glass screen door at 11pm when I came home o.O