Riddle #676

Question: 500 is at my end and my start, yet 5 is at my heart.
The first letter and the first number make me complete.
My name is that of a king.

What am I?

Question: What fish only swims at night?

Question: What kind of mouse does not eat, drink or even walk?

Question: What has a bed that you can't sleep in?

Question: What tastes better than it smells?

Question: What goes in the water black and comes out red?