Rosy barbs will suck down algea like spaghetti. I had some hair algea in my first planted tank, went and got two rosy barbs and introduced them into the tank (which at the time had no fish in it) They tore around the tank and sucked down every piece of algea in about 2 hours. They are beautiful fish, and I loved them, but when I started the bigger planted tank, and moved them into that, there was no algea. And they ate my plants.
So, If you wanted to get a pair, I would advise watching them very closely, and if they start eating your plants take them back to the fish store. They will eat algea pellets, but the algea pellets don't stop them from eating the plants.
Jan