Otos will graze on broader plant leaves, but amano shrimp are unparalleled in their algae eating ability. However the specific types of algae you have also will dictate what algae eaters you use.
That being said, I don't think Otocinclus are a viable long term option for a 5 gallon tank. They are very social and like to have space to swim. Probably a 2' or 3' tank would be the minimum.
That being said, I don't think Otocinclus are a viable long term option for a 5 gallon tank. They are very social and like to have space to swim. Probably a 2' or 3' tank would be the minimum.