Betta chase

[Bettas are Betta]

Why does my friends bettas always endup chasing her new neon tetras around and hes nipping at them and they look pretty freaked out

[Oldfishlady]

How big is her tank?

Often in too small of a tank without much cover the Neon tetra can't get away or out swim the more aggressive Betta. More cover or a bigger tank may be needed
He is acting like a Betta......

[Bettas are Betta]

ok thanks for the advice!

[Phoxly]

I introduced my betta AFTER the Tetras so the Betta wasn't territorial. You can try taking the betta out an putting him in a quarantine tank for a day or two then putting him back in.