One Oscar Per Tank

Question
Dear Dr. Coleman:

A website I peruse (Oscarfish.com) is conducting a poll regarding successful attempts at keeping more than one Oscar in a tank under 250 gallons. The results -- as of 19 responses -- vindicate the advice you often give: almost 70% either failed or would rather not attempt it. (http://www.oscarfish.com/viewtopic.php?f=1&t=82073)

Why is this? Is it purely a function of territoriality (given which the question ought to be why do two Oscars ever get along, not why they clobber each other)?

There's something sad about the anthropomorphic tendency to ascribe loneliness to a single Oscar, then remedy it with the disastrous solution of adding another. It seems many fish stores take an oath to perpetuate this.

(May I share your answer with the site?)

Best,

John

Answer
Hi John,
 It is unfortunate that people think that just because we (people) don't often like to be alone that other organisms are the same way.  Oscars are highly predatory fishes. They need to find and eat other fish to survive. If you put two in a tank, then you just made life a lot harder for the one that was in there.   Sometimes they will get along, but that usually only happens if they were raised together, or if they are a mated pair.  If they are just two males, then odds are that one is going to get rid of the other.  On top of all of this, oscars, like many large cichlids, seem to get a lot of satisfaction out of interaction with humans and can easily recognize individual people as being different from one another.

Yes you may share my answer.

-- Ron
  rcoleman@cichlidresearch.com
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