Usually, when a tank starts to grow algae, it is a sign that something is out of whack. You have a planted tank, so the plants should be using up the nutrients in the tank. But, there are clearly some nutrients left over for algae. Usually to control algae, people cut back on the amount of light, but you may not be able to because of the plants. Doing more water changes to get rid of the nutrients the plants aren't using would help. Finding a way for the plants to make better use of the nutrients (by adding CO2 or something) could also help. (but research that and do it right, so you don't poison your fish with it). Just throwing in an algae eater and hoping they will eat the algae doesn't usually work. Most really don't eat much algae, and need to be fed, and create waste (more nutrients) which grows more algae. There are a few types which will eat lots of algae (ottos, BN plecos and Rubber lips come to mind), but many don't. So, usually figuring out why the algae is there and fixing the problem is a better plan of action.
Emily