The first thing my neighbors said about my ponds is "won't there be a lot of mosquitoes"? I talked about how the goldfish would eat them but just got back disbelieving looks. It wasn't until I found how about mosquitofish (Gambusia affinis) and told my neighbors about mosquitofish eating all the mosquitoes that I got that knowing look back "yes, they'll take care of those mosquitoes". Names apparently are important. The goldfish would have done just a good a job but just didn't have the right name.
BTW, I really like mosquitofish as pets. Especially is a tiny pond. Hard workers, interesting life cycle, and fun to watch when feeding if you get right up close. I would grow mosquito larvae just to feed the mosquitofish in my tiny pond. Watching a 1/4" mosquitofish kill and eat a 1/8" mosquito larvae is an amazing battle when viewed with your nose to the water. They also would come to the surface and flick themselves several inches across the surface to escape others. Not jump mind you, but flick, so they stayed not far above the surface. I'd guess their tiny bodies allow them to use surface tension to perform this feat.
Moving Water - Mosquitoes can't lay eggs or grow in moving water.
Well, define moving water. Some people think a 50gph pump in a 1000 gal pond is moving water and therefore can't have mosquitoes. But take a close look at the fasting moving moutain stream you can find. There's always going to places near the bank with calm water. Since a steam is moving you won't see many mosquito larvae since they would get washed down steam and of course fish and bugs will eat them too. But their will still be some mosquito larvae the make it to adults.
All water gardens are suitable for mosquito larvae no matter how big a pump you have.
It's a myth that a pond will increase the mosquito population. Instead a pond with small fish like goldfish and mosquitofish will act as a mosquito sink. Eggs
laid in the pond will be eaten instead of becoming adults. Without the pond the females would have surely found another place to lay eggs where they might have become