I don't see why not.
Your tank looks reasonably stocked, and all of the fish in it are peaceful.
I would recommend a bristle nose pleco, they are supposed to be very good algae eaters, and should get along with your other fish. Plus they are relatively cheap.
But also, if you want to get a bunch more, you could get a school (4 or 5) of otocinculus , which stay small and are good algae eaters.
Or if you wanted anything exotic that is a good algae eater, you could get a Queen Arabesque pleco. They are very showy and fairly good algae eaters. The only problem being they cost a little bit more than the others I mentioned (I bought mine for $35).
Just remember, Algae isn't going to kill your fish, so it isn't a big emergency. If you want, you could just start turning the lights off earlier to prevent further algae growth.