yes.
but you might want to do some research on what fish can go in the same tank with fighter fish (Bettas).
I have 10 other fish with my betta and so far he has only killed 1 platy over the holidays when my nan was looking after the fish.
:)
Fighting fish are territorial and can be very aggressive, they will kill other fish if you put them in the same tank.
Other fishes
Not all fish travel together - top-chain predator fish are not uncommonly solitary, and even territorial - but smaller prey fishes - and the includes flying fish - will commonly school.
Yes, you can just not have 2 male bettas together.
They will fight until either you remove one or one kills the other. That is the reason why they are called "fighting fish".
Monday
The "flaring" of the gills is simply a way for the fish to look larger and more threatening. It is both defensive and aggressive behavoiur.
Angelfish, fighting fish and other bigger fish would. They would do it more often too if the guppy looked weak or less strong than other guppies.
The turtles will eat the fish.
Beta fish don't get along with other fishes, they will attack any fish that they see as a threat. If you buy a female and a male beta DO NOT put them together.
The Fishes...
yes blue fighter fish eat other fish and bites them slowly untill they die