Red on black-beard algae is a sign its dying. Fish that eat plant matter can eat it.
The problem with cutting off the leaves that have it, is that it will just take hold on the lower leaves now that they are not shaded. Anubias are not the fastest of growers, but the algae indicates an imbalance in light, carbon, and other nutrients.
How long are your lights on per day? Does the tank get any direct or indirect sunlight? Does your ammonia and nitrite levels stay zero? What is your reading of nitrate before you do a water change?