A little blurry, but this is a mating pair. the female is on the left, and the male is on the right, showing his manliness by flaring out his fins and bloating his gills to impress her. They do a funny dance where they go nose-to-nose & move foreward an inch, then back an inch, repeatedly about 4 or 5 times, then they both open their mouths and put them together for a while.