I don't see anything visible that the riccia is attached to. In my nano tank, I used small pieces of slate and wrapped fishing line around them. What are you using in your tank?
Two 1 GA desktops, a 5 gallon, a 2.5 gallon, a 10 gallon, a 20 gallon, a 25 gallon, and two 75 gallon tanks, all planted.
I am an expert on algae, so ask me if you have questions. I know how to grow it, just not how to get rid of it.