I just got a goldfish and the Sims

[ShadowHM]

The quickest way to kill your goldfish is by ammonia.  That is the result of (1) overfeeding, (2) not changing water enough, or (3) both.

Ammonia builds up from rotting food or from fish poop. 

in a friend's life.

She had decreed that the fish had to go. Her husband reluctantly agreed.

He dropped the fish in the toilet but did not flush.

She waddled her 8 1/2 months pregnant self into the room and slowly lowered herself onto the throne. The very second her urine hit the water the fish started jumping madly trying to escape. They inevitably began hitting her in a place where she had no expectation of attack. Due to her awkward condition, she was not able to rise with the alacrity she wished for.

It was traumatic. Her feeling of betrayal was not improved by the laughter of her husband when he heard the screaming and found what had caused it.