sounds like he is sick or just could be resting have you done a test to see how the water is? is there a heater in your tank? because there the norm of why he could be getting ill.
Some betta do this alot. But if it didnt do this before then something might be wrong with the water. My sister has a betta that all it does it lay at the bottom. Hers isnt dead and shes had it for a year now. But i would change the water for it and see if it gets any better.
sounds like he is sick or just could be resting have you done a test to see how the water is? is there a heater in your tank? because there the norm of why he could be getting ill.
is the tank cycled
does the tank have a filter and heater
What are your ammonia and nitrite readings?
Some betta do this alot. But if it didnt do this before then something might be wrong with the water. My sister has a betta that all it does it lay at the bottom. Hers isnt dead and shes had it for a year now. But i would change the water for it and see if it gets any better.
First thing to check is the water quality and temperature.
If the water is polluted, or too cold they just sorta sit on the bottom, and die.
Ian