But in your home tank, there's no bacteria to be found. You have to introduce it, and that's where a lot of goldfish owners slip up because you can't just buy a fish the same day you get your tank.

The cats were allowed back in once the goldfish was set up in its tank, and one of the felines was pictured peering inquisitively at the new arrival. The fish has now been named Alice after a text ...

But they're not just consuming what other fish rely on to survive — their voracious feeding time actually kicks up mud and sediment ... should keep that goldfish in its tank.