Hi, so I tried doing some research before when he did this, and got no where. I figured it was just 'cause we'd moved the day before a few days beforehand my friend's little sister scared him by putting her face against the tank. So when he stopped I figured that was that.
But now he's flaring his gills again. Just his gills, nothing else. He does it even when I feed him. I changed to water less than a week ago, and he has what I think is a bubble nest (certainly looks like it, a bunch of bubbles in a corner). I've tried just standing far away to see if he chills, and he doesn't. I've tried playing with him by dragging my finger along the tank, and he flares at it as he follows.
He seems perfectly normal otherwise. His fins are regrowing (I had cats at my parents and one liked watching him and batting at him, causing stress a bit) and look almost fully healed. The tank is five galleons, with a filter, conditioner, and two live plants. The heater is on, so the temp is 76.
This is odd behavior, since he never did it before the move. I usually change the water bi-weekly or if it gets low. I used to do it weekly, but he hates coming out and freaks, turning really pale and frantic, so I figure it's okay to have a longer change people due to the plants.
I want some opinions to see if it's anything I should be concerned about. I don't want him sick or unhappy.