The strange behavior keeps going on.

Question
Hello Ron,
I just wanted to say that all of the information that I have gotten here I have used. I have a bought a new 55 gallon tank and have gotten a new filter and check the water daily. Water parameters are perfect, I also do weekly water or bi weekly water changes. My fish also have a varied diet of greens, pellet food, and a new food that I have just started dried krill. My fish are about 8 to 10 months old and about a month and a half ago the tiger the larger of the two started to be very aggressive. It really did some bad damage to the red one, i separated them in the same tank right away.  I gave them trial periods of being together to only separate them again. Well this time the tiger is being aggressive but not as bad the red only has a few minor scrapes and it is been like 3 days. But the red has taken to hiding when the light is on and will swim when it is off. They have also have been vibrating tails again and doing like a little dance again but mainly when the light is off. Strangely the tiger is alot less aggressive when the light is off too. Are they just stressed out, or are they fighting for space right in the tank? Or are they getting ready to mate, and most of all should I separate them again. I can't stand it when they are separated they stare at each other through the divider like they are heart broken. What should I do for these guys they are about 8 to 10 inches long and can cause some serious damage if they want to.
Thank You,
Heidi

Answer
Hi Heidi,
  The difficult thing is that fighting and courting in large cichlids looks exactly the same. The only difference is the outcome.  Both are highly physical and the one (courting) can change to fighting instantly with very bad results.   The general rule that I follow is that if the two fish are going at it face to face, then things are alright. If one is chasing the other incessantly, and that fish is trying to get away, then you need to separate them.

  The decision to separate them or not is yours.  If you keep them together, I would keep a very close eye on them.  

-- Ron
  rcoleman@cichlidresearch.com
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