Help!! Advice? Clown fish and hang on overflow

Any way to build a screen in front of the overflow?
Unless you can train him not to surf the overflow, I think a physical barrier is the only way to stop it.

 

Get some Gutter Guard from Menards, cheap and you can cut to shape, and it doesn't easily block flow. You might still have to remove & clean, but I use this for this exact purpose, and also as a surround in a in-wall tank so that fish that jump don't end up carpet surfing around the back or sides of the tank

https://www.menards.com/main/buildi...5-c-5812.htm?tid=-7000026171512533593&ipos=11