firefish

Question
hello I have a firefish in a 15 gallon tank w/yellow tail damsel and pajama cardinal. I have a few questions about firefish. does there long dorsal fin have a purpose. also my always goes away hiding at 9:00pm even if the light is not off and I don't see him till morning is that normal. also would get along with a blenny or shrimp goby. thanks

Answer
Hello Ben,

Indeed, the long fin on top (Dorsal Fin) has a purpose.  It is used to flick up and down and to signal other firefish.  It is a means of communication.

The Firefish will hide and yes, it is perfectly normal.  They are also known for jumping out of aquariums.  

He will get along with a Blenny, and a shrimp goby, both, however depending on what kind of shrimp goby you get, the size may be an issue down the line.  I would get one who does not grow more than 3 inches in length.  This will assure no pecking on the firefish.

I certainly hope my answer has been both, professional and friendly and that it helps you out.  Please feel free to ask a followup question if you need to, and I will do my best to get back to you as soon as possible.

Happy fish-keeping!

Renee