You're gonna have to have a mud bottom pond, like the salamander would have out in nature, plus lots of hiding places at the edges of the pond. Salamanders don't live in water, after they're done being newts, so they need a space that's on land. Plus source of food, shelter from animals of prey, etc.
Personally, I don't think it's a good idea to mix fish with animals you hope to keep alive - salamanders, frogs, lizards, baby birds - all those things a fish would eat if it could get at it. Even a large salamander is going to be small when it's young, and the babies have to be in the pond with the fish until they metamorphisize into adults.
Also, the critter is going to be hiding most of the time, so you and your husband are not likely to see him and enjoy him much, anyway.
I'm thinking you might be better off keeping him in an aquarium set up in the house - with proper heat, lighting, food, and all of that, of course. If you want to keep him outdoors, I'd build a seperate, totally enclosed and secure, cage, just for him, and include all the features of his natural habitat.