Does he flare all the time? My guys will flare for a little while and do their dance, and then go back to whatever they're doing. They flare at least once and hour, but I don't believe they're stressed or anything. When my brother's fish was too stressed, she just stayed at the bottom and showed her stripes, wouldn't eat, etc. so I figured as long as they weren't doing that, they're pretty happy. As long as he's not hurting himself flaring, I think he should be ok.
Wish we could just ask them and find out! =P