I'm not quite understand what to straighten the castle mean. Pls help.
The text is:
A goldfish just wants you to feed them and clean the bowl. And, oh yeah, straighten the castle while you're there!"
People sometimes put a small replica of a building, often a castle, in their fish tank or bowl so that the fish can swim in and out of it, it looks more interesting than just watching the fish swim round and round.