What causes a Cichlid to dig

Question
Hi Ron
On two recent occassions one of the cichlids in our tank has dug the gravel up, totally moving it from one spot and placing it in a mound elsewhere.  The first occassion it was an electric blue and this second time an orange peacock did it.  I assume it has something to do with mating, however we don't have two of the same type of cichlid in the tank. The cichlid also becomes very aggresive to others.  Can you shed some light on this behaviour?

Answer
Hi Noel,
  Cichlids and particularly male cichlids will often dig alot and move gravel around.  A male does this to establish a spawning territory.  The fact that you know that there isn't a female in the tank doesn't mean that HE knows that there couldn't be a female coming along any time and male cichlids are forever hopeful....

-- Ron
  rcoleman@cichlidresearch.com
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