Funny flagfish behavior

[Galaxie]

Just a little tale about my Flagfish:

I put a single female 2-inch flagfish (jordanella floridae) in my 10g tank about a month ago. From everything I read, the flagfish is a very very peaceful fish. This flagfish started getting into the habit of chasing around the peppered cory cats (about 1.5-inches). Corys are pretty shy, so they looked like a couple kids chasing each other around the playground. I was ready to separate them, but I sat down and watched them carefully one day. It seems the flagfish is tailing the corys and nabbing all the little bits of food that the corys stir up as they rummage around in the substrate. Very interesting/ intelligent behavior I thought. Originally, I thought....great, I have the world's only aggressive flagfish! But, she's just being a little scavenger. Overall, a very interesting fish. Not quite as colorful as the males, but definitely a unique personality. She will eat anything too. Flakes, betta bits, sinking carnivore tabs, cucumber, and evidently cory table scraps.

 

[reziztor]

Flag Fish are territorial in small aquariums. Everything I have read about them states this.

They can be mean, even in larger aquariums... They like to be in large groups. Then they lose their territorial instincts. I've been keeping them for years.

 

[Galaxie]

Unfortunately, most every article I've read has conflicting information. For the most part, the males can be territorial when kept in groups. When breeding they are quite aggressive....even to their mate.... almost like cichlids. But Flagfish are killies. She doesn't even seem to notice the 10 neons. When kept alone, they show no more belligerence towards other fish than a typical molly.



Great Flagfish article