Very good algae eaters are Bristlenose Catfish and Siamese Flying Foxes (the true ones). However, I'm afraid a 10 gallon tank is much too small for them. A good alternative would be a few Otos (if a tank is not overstocked). As for Cories, I'm sorry I don't know much about them - but many others on Fish Lore surely do
Do you have any algae in your tank? Because even if you do, that is not enough for any algae eater. Their diets need to be supplemented with algae tabs or wafers and other foods for algae eaters. My Gold Algae Eater, for example, even eats brine shrimp.