Originally Posted by Dav3
With a tank that small water changes are easy and all you need to keep nitrates and phosphates in hand. And thus no need to worry about algae and no need for a clean up crew.
That being said if you want "clean up crew" then get livestock you would like to see and look at. Any extra will just add to your nitrate and phosphate issues.
Whatever you add to the tank will have to have food to sustain it, or it will slowly starve to death. A cleanup crew is not necessary at all, and you can have a perfectly healthy tank without any snails, shrimp, crabs, or starfish. I would not look to online vendors for advice, because what they do is sell livestock. Like Dav3 said, get a few things because you like to look at them and want diversity in your tank, but not because you feel you need them. The cleaner wrasse despite the name is not a creature that helps eat uneaten food and fish poop, it eats parasites off of fish in the wild, and in many cases, will not eat prepared food in closed systems. As also stated, not good for your application.