We just got a new 10 gallon tank, it's up and running, we only have 1 goldfish. What kind of fish can go in with goldfish? My husband wants to get tropical fish.

I agree with Skwishee.  No more fishies for a tank that size, unless you have a 10 gallon with only tropicals in it. Goldfish and tropical fish do not usually go together too well because they have different heating requirements (as they like much warmer water that goldies, which are cold-water fish) and are known to pick on the peaceable goldfish. This causes stress and irritation on part of the goldfish, so it's best to just leave that little fishy by himself in that 10 gallon. You will also discover very quickly that goldfish grow FAST and BIG. As in, 6-8 inches for fancies and 12 inches + for single tailed varieties.