convict and green terror

Question
I have a 55 gallon tank with a black convict and green terror which have been together for about 6 months. The fish have always got along but the convict ruled the tank. The green terror is larger than the convict. i got up one morning and the convict was hiding under the filter and was very dark in color an did not look right at all and when he came out the green terror chased him. which was weird because it always the other way around so I took the convict out of the tank and put him in a tank by himself and he looks alittle better but his color is not the same. I am wondering once the green terror realized that he was bigger and that he wanted to control the tank is that normal behavior? I don't want anything to happen the the black convict i really enjoy him the bestbut I don't know if he is sick or the green terror did something?

Answer
Hi Crystal,
 I suspect you are right in that the green terror is starting to feel like he should own the tank and you are seeing the results of that.

 If you do decide to put the convict back in, the key is to have LOTS of structure in the tank, e.g., wood, rock, plants etc so that the convict has many places to hide if he feels the need.

-- Ron
  rcoleman@cichlidresearch.com
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