Strange you ask this, because I just read this article on my favourite invert site:
http://www.planetinverts.com/why_shrimp.html. Check out that site for more invert info!
For a 5.5gal tank, there isn't really any algae eating fish that fit. Otos would fit - but since they are fragile it's best to have at least a 10gal for them.
The fishlore database doesn't have all freshwater fish in it. Most common fish are listed, but not much more.
The secret to algae control is nutrient control - you shouldn't need algae eaters if your tank is properly stocked and balanced.