My Betta keep sitting on the...?

I have 2 male fighters. One keeps sitting on the bottom of the reservoir and not eating properly. Whats going on?
he got his (a)ss pulse. Males will almost always fight respectively other (hence the name siamease fighting fish) and shouldnt be house together, put them in seperate tank or use a divider or one will be dead soon
If you have them in one tank, remove them or you will find them war, and I mean fighting to the death of one and the other one messed up and possibly dying following on.

If you want a betta tank, and want to add more to it, add live aquarium plants
Answers:    Number one you CANNOT keep two male betta's contained by the same fish tank. I'm surprised that one isn't dead. They will annihilate each other. The one betta who is on the bottom of the tank and not eating properly is scared out of your wits trying to be invisible. One or both will die if you don't seperate them into seperate fish tanks. And please don't ever put two male betta's together again. You also cannot maintain a female and male betta together unless they are mating. they can be together for perhaps a day or two. The female will kill the masculine.
separate them then use different food for a while until her starts eating as a rule then slowly switch him back onto his other food or stay on that same food and if that dosen't work sori u only have a sick betta

hope this helped
The fish are fighting. Those fish should never be housed together.
the one not eating is intimidated by the other, they shouldnt be housed together, separate them
Ok first, gain two tanks, because they fight. Also, what is the size tank. And how thaw out is the tank? If it doesn't have a heater, you involve to get one.
how big is the reservoir if the tank is huge it should be ok but if its not 2 tank my man 2 tanks
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