Denitrator - what is it, and do I need it?

[txrunning1]

On the 75 gal used setup I just purchased, I got a denitrator. I have no idea what it is, or what it is good for. I am sure that some people use then, but I need more info on it. What would you do?

 

[nosmada]

i found this link for you
http://www.geocities.com/Heartland/3363/denit.htm