Today I got 2 new bettas, Angelo and Avocado. Angelo never seems to close his mouth. Its always open just a little and his gills kind of stick out alittle too. Is he sick or was he just born at way?
Open mouth can mean he has something lodged in his mouth, so check him carefully, also gill flukes can cause the gills to stick out and have mouth problems.
I see sorry thought you meant the mouth was wide open, read it wrong, if he's eating that ok, but if the gill flaps are sticking out it can mean bacterial,parasite, or fungus, so keep an eye on him.
If he had something stuck in his mouth, he might not eat. It's common for them to not eat for a few days after they've been introduced to their new tanks, too.