Actually, mosquitoes will never breed in moving water. They prefer stagnant water. Of course, adding fish that will eat them is not a bad idea. Mosquito fish and guppies are often used for this purpose. Mosquito fish are a little more nippy than guppies which is why I prefer guppies in this case.
As far as algae is concerned, there are many various methods to minimize them. UV sterilizers, barley, plants and cutting off lights (more practical for indoor ponds and tanks) to name a few. Adding several plants will allow them to compete with algae for foods. I've noticed in my experience the addition of hornworts and Egeria densa tend to eliminate the green floating algae.
With UV sterilizers, the algae must pass through the system in order to be destroyed. In this sense, it cannot destroy filamentous algae, green spot algae and diatoms that will never pass through the system at all.
Do you plan to use the pond at all?