Parrot cichlids becomming arressive

Question
Hello
I have two Blood Parrot fish I don't know too much about them. It’s very hard to find information on them. Right now they are living in a 20-gallon tank and their tank mates are three Glass catfish, one Butterfly Pleco, one Dragon/Violet Goby (about 6 inches long), one onion snail and one zebra snail. I have had the Parrotfish since December 2005, but now it is as if one of them has become rather aggressive just out of the blue. I don't know why or what to do, it is constantly chasing the other one into the corner at the back of the tank, I feel really bad for the one that keeps getting chased and I am worried that it will become stressed, stop eating and then die on me.

Regards
Christine


Answer
Hi Christine,
  Most likely the aggressive one has matured to the point where it wants to breed, but the other one isn't interested.
You will need to consider separating the fish or at the minimum, putting a lot of structure in the tank. Structure is stuff like plants, wood, rock, etc such that it breaks up the space and gives the weaker fish a way to get out of the view of the other fish.  

-- Ron
  rcoleman@cichlidresearch.com
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