Translation of "Decaying" in Spanish

Our democracy is decaying.

Nuestra democracia está en decadencia.

His memory has been decaying because of age.

Su memoria ha ido decayendo a causa de la edad.

Like that awful taste in your mouth, the smell of burning, decaying fish,

como el horrible sabor en la boca, el olor a quemado, a pescado podrido,