dying frogspawn

I just got home and my frogspawn looked happy this morning but now it looks like this? What happened and what should I do?

Hi guys! I have a beautiful frogpspawn here had it for about 3 weeks now and its stunning. Im a little worried its starting to die off. Im not sure if im paranoid or something I need to do something about. There is some receding on the right side. Everthing else in the tank is doing great. Any...