They grow up to 15 cm ( 5.9 in ) in size , but typically attain a smaller size of around 12 cm ( 4.7 in ) .
Their colours change depending on their mood , but subordinate males do not display bright colours .
males grow up to 15 cm ( 5.9 in ) in size , but typically attain a smaller size of around 12 cm ( 4.7 in ) .
Their colours change depending on their mood , but subordinate males do not display bright colours .