Angel fish question

Question
Hi, I have 18 gallon tank with many live plants, rocks and 8 angel fish. My angel fish are all ok but I just want them to breed. I donot know thier gender, can you please tell me how will I make them breed or encourage them to breed? My angel fish are very large and healthy, but there is an unusual thing about them, my angel fish are aggresive to each other, they were not aggresive when I first brought them but after 5 months suddenly they are aggresive. They are not very much aggresive. Each angel fish is disturbing another angel and the same disturbing another. My water conditions are fine. But can you please help me, because I want them to breed?

Answer
Hi Amy,
 Actually the aggression is the first sign that they are starting to think about breeding.  Like all cichlids, angelfish become territorial when they breed and it takes aggression to make and hold a territory.

 When you say that they are "large", how "large" is that?  An adult angelfish (not counting the fins) is about 4 inches or so high in the body.  Are yours that size yet?

 You cannot make them breed.  All you can do is provide conditions in which they decide that they want to breed.  

 Do you have any slate in the tank?  Angelfish prefer to spawn on vertical surfaces and a nice piece of slate, resting almost vertically against the wall of the tank is an ideal egg-laying surface for them.

-- Ron
  rcoleman@cichlidresearch.com
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