My personal preference is going to be to stop the algae growing in the first place, through control of lights, fertilization and CO2 as needed.
next would be treating with a mild algaeide, like Excel or CO2 booster
Finally, if you do need to get an animal to control it, really depends on the type of algae, the size of the aquarium, and the other inhabitants of the aquarium; Nerites can work, so can otocinclus, japonica shrimp and other animals, just get something you would like to have in your aquarium, rather than using the available bioload to get a janitor.
How long are your lights on? More than 7 or 8 hours can help many types of algae. I use a timer.
New tanks often get brown diatoms everywhere but they can go away after several weeks without any treatment.
I agree with dougall & would caution that no 1 animal eats all kinds of algae or enough to get rid of it all. Some, like otocinclus & nerites, may have a hard time switching to a different food once their preferred kind is gone.