Clean Up Crew

Do you want something to eat left over food? Only there shouldn't really be any if you are feeding the right amount. You could try a shaol of one of the dwarf species or corydoras; that's 6 of either panda cories, pygny cories, habrosus cories (in the fish profiles on here as salt and pepper coreis) or hastatus cories. The other species would get too big for the average 110 litre tank. But you would need to feed sinking food for cories as they can survive on just left overs.
Or to eat algae? Again, better to find the cause and treat that. But nerite snails make good algae eaters and they can't reproduce in fresh water to you won't get overpopulated. Though if you had a male and female they would lay eggs all over the decor (which won't hatch).

Shrimps might get eaten as swordtails and mollies are quite big fish, and even the gouramis might go for them. If you could find fully grown amano (japonica) shrimp anywhere, they should be OK as they are quite big.





Just to check - you don't mean you want something to clean up fish poo? Because there are no fish/shrimps/snails that will do that.