Sick clownfish

[Jay Hemdal]

Is there anything else I can do?

Yes - based on the fish's history, I would consider a praziquantel treatment. That's safe for your invertebrates, and will treat for possible flukes:

Dosing Praziquantel (PZQ)

Using Praziquantel (PZQ) to treat flukes Overview In the early 1990’s, a researcher at the New York Aquarium published a paper on using Praziquantel (PZQ) to help control flukes, a parasitic flatworm. Also known as monogenean trematodes, these fish parasites can cause significant mortality in...

www.reef2reef.com