a betta can live happily in a bowl with no filter. i have three in that living condition. i find that bettas are happier in a larger tank with a filter, BUT they often wont eat in a larger invironment.

i feed mine once a day. they get dried blood worms, and three pellets each. mine are piggies... three times a day is way to much for a betta... most bettas dont even eat once a day.

bettas flare their gills when they are stressed, want to impress their mate, are angry, or when they are about to attack.

it is normal.