Question about angry fish

[bbauer]

I have a lunar wrasse that is very territorial of my tank and whenever I try to add a new fish to the tank he chases it around and usually the new fish dies from stress. Do you think I could Remove him from the tank into an existing quarantine, add the new fish to the display tank and then add the wrasse back into the display tank after a week of isolation.

 

[NaH2O]

That sounds like a reasonable possibility, and better yet would be to isolate the new fish to quarantine to make sure it is in optimal health before being added to the display. What size tank? What are the current inhabitants?

 

[moortim]

how attached are you to the wrasse? I have always just tried to remove the problem fish rather than make them cooperate with each other. Just a thought........

 

[bbauer]

the tank is a 110 tall and unfortunatly the wrasse is the only fish I currently have in there. About a month ago I had a catastrophe and all my fish died except for the wrasse. So he has been the only one in there and I believe he has claimed the tank for himself

 

[wrightme43]

Time for the reNeducation camp. LOL
Probley best to remove him and trade him to LFS. With the understanding he needs to be in a tank with more aggressive fish.

 

[steve-s]

How old/mature is the wrasse and what length?
What fish have you been attempting?

The problem with this and many species of Thalassoma is the older they get, the less tolerant they become. While they do great with any fish added before them (even other wrasses), anything later on can be a bit tricky. There is also the tendancey with this fish to be very "playful" and inquisitive. It may appear the wrasse is chasing but may simply be playing. The two types of fish I find Lunar wrasses have the most problem with is blennoids and goboids. Adult Lunars have been known to kill them on sight.

If this is a juvenile wrasse (which is the only way to purchase this particular species), most of your issue is play. In which case removing it/returning it until your other fish are in and then re-introducing it later will work. If this is an adult Lunar, you need to be very wary of what you can introduce. The tank size is not that great given it's potential size and activity level.

Cheers
Steve