Tiger Oscar behaviour

Question
Hi i recently set up a big tank for 4 Oscars, 1 large tiger 20cm, 3 smaller around 8 cm and 1 large pleco 25cm, we moved them all into the larger tank last night and the largest oscar went nuts flaring his gills, amazing colour display flashing orangey yellow and charging the front of the tank and mouthing at the others, the pleco was defending the others and bumping him. This went on for about an hour, this morning he seems calm and has one side of the tank and the 3 other oscar seem to stay on the other side. Is this normal behaviour it was an amazing display
regards
jennifer

Answer
Hi Jennifer,
 Yes, it is "normal" but it also suggests that life is not going to be calm in that tank.  By the way, 20cm is still a small oscar.  An adult oscar is more like 30-40cm.  Oscars are fascinating fish but they do not play well with others, including other oscars.  It is not out of the question for your large oscar to eat the smaller ones so keep an eye on things. You can reduce the aggression by making sure that the tank has  a LOT of structure (wood, rock, plants) to divide up the space.  

-- Ron C.
  rcoleman@cichlidresearch.com
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