How do you guys get your males to flare?

This guy just would not flare whatever I did. He thinks his reflection is interesting, but never got pissy at it. Videos of another male flaring held up to the glass? No good. My finger? Just a fun toy to chase.

Then I saw my red boxcutter on the counter and thought “maybe….” Turns out, he ONLY flares at my boxcutter 🤣😭 guess I can never get rid of it..

Side note, Yes, I know hes fat. Hes still fasting from stealing an algae wafer that was intended for the snails while I was asleep.