Angel fish behavior

Question
Hello.  I have a pair of angel fish - unsure of sex - one is a marble and the other a black lace.  They were put into the tank together about 4 months ago (size of a dime then) along with a blushing.  The blushing died first night.  These 2 have gotten along fine thus far.  The last 2 nights I have witnessed the marble being very aggressive toward the black.  I am relatively sure that they must have reached an age or size of sexual maturity.  My ? is:  Is it more likely they are a breeding pair or 2 of the same sex?  The aggression is quite strong - including torn tail and missing scales along side of black, swollen mouth, etc.  The black still seems to prefer to be by the marble, it doesn't seem very afraid of the marble and the abuse isn't constant - but it is doing damage so I am concerned.  Thank you for any advice.  Sonja.

Answer
Hi Sonja,
 The tricky thing about breeding cichlids is that fighting and courting look pretty much the same.  The real difference is how it ends.  In fighting, one fish ends up chasing the other.  In courting, they end up spawning.  Both can be quite violent and include the symptoms you describe.  Keep an eye on things. If one of them appears to be trying to get away constantly or hide, then you need to do something about that.

-- Ron
  rcoleman@cichlidresearch.com
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