chilid has lost his color and paces the tank back and forth

Question
Ron,
The stripes on the cichild are horizontal. His back fin is spotted,his top fin is all the way down his back and has horizontal stipes also. He is almost a solid black color now! I think he is angry. He has a very mean look to him now! Can it have babies if it's the only one? Also, i have a plant a kinda open rock and then the bridge thing that he shares with the crab! I don't know what to do? But i don't want to get rid of any of the fish, they are all so neat and interesting. The placostomus keeps the tank pretty clean and the cichlid was very pretty. I wish i could show you a pic, but i don't have a scanner or a way to show you him. Why won't he mess with the other two fish?
thanks
stephanie
-------------------------------------------
The text above is a follow-up to ...

-----Question-----
All i know is he is an african chilid about 3 inches in length and now he is very aggressive to the placostomus, and only that fish! For about the 1st week we had him he was a bright yellow with black stripes and some dots and now he is dark black on the bottom and kinda brownish as the color moves up on him? What would make him hate the placostomus now, after being in the tank with it all this time! He tries to eat at his tail and chases him all over the tank. We also have a very tiny puffer fish and a fiddler crab and he doesn't mess with them. He shares a hideout with the crab. The placostomus doesn't mess with him, but now he won't leave it alone! Do i need to separte them?
thanks
stephanie
-------------------------------------------
The text above is a follow-up to ...

-----Question-----
i would like to know why my african chiclid has lost his color. It was bright yellow with black stripes and now he is dark black on the bottom and kinda brownish toward the top and he keeps trying to attack my placostomus and he paces the tank back and forth? What would cause it to turn that color? Is he sick?
thankyou
-stephanie-
-----Answer-----
Hi Stephanie,
  Cichlids change color all the time for many different reasons.  Do you know which kind of cichlid he is?   Some
change from a juvenile color pattern to an adult color pattern as they mature.  Others will use color to indicate their mood, e.g., feeling aggressive/territorial versus feeling shy/vulnerable.  It really depends entirely on which species you have.

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>

-----Answer-----
Hi Stephanie,
   It sounds like he is interested in mating and so when he tries to find a nice area on the bottom to make a "nest"/courtship area, he keeps running into the plecostomus, so now he figures the plecostomus has to go.   You can either remove the plecostomus or provide him with more places to hide.  A nice piece of wood is often great for a plecostomus.  

 By the way, when you say "yellow and black stripes" do you mean horizontal (ie., along the body) or vertical? Are the stripes on the body or on the fins or both?

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>


Answer
Hi Stephanie,
 No he can't have babies all on his own but only you and I know that there isn't a female somewhere in that tank -- hope springs eternal for many fish, i.e., he is hoping that somehow, someday a female might appear and he is getting ready.

 I can't say why he doesn't bother the other fish, but I would be grateful that he doesn't.  

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>