Orange Parrotfish

Question
Hi Ron
I have a Orange Parrotfish whichi've had about 7 months a couple of days after i bought him i put a diamond shark in with him they got on really well and i and no problems,until i went on vacation a couple of weeks ago and came home to find someone had been over feeding my fish and unfortunately the diamond shark died. i cleaned the tank out but the Parrotfish developed white spot. i got treatment and the white spot cleared but not my parrotfish is very aggressive towards me and eery time i turn the light on is the tank he rams the glass i have also noticed dark spots on his Finns, the girl in the petstore said he might be lonely so i bought a bala shark and within three hours the shark is in a bad way I've had to remove him can you help me please???
Kind Regards
Karen O Neill

Answer
Hi Karen,
 First, fish generally don't get lonely.  Aggression is usually a sign of territoriality and often is a sign that a fish is doing very well, i.e., the opposite of something being wrong.   

 It may not have been overfeeding that killed the diamond shark, it easily could have been the parrotfish.  As they get older, they get substantially more territorial and more aggressive as a result.  

-- Ron
  rcoleman@cichlidresearch.com
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