Fish aggression to new addition question.

tanked37

New member
So I know that adding the most aggressive fish last to the tank is advisable, but not always possible.

My situation is that I have a desjardini sailfin tang that's been in the tank for 1 year. I'm adding a small yellow pyramid butterfly after having been in my QT tank for almost 6 weeks.

I put the yellow pyramid in a mini-QT tank that hangs over the side of the DT so the other fish get used to him. He was in there for 3 days and I let him out the other morning. Everyone seemed to get along just fine and that evening there was no signs of aggression.

Anyway, this morning I wake up a the sailfin beat up the pyramid and he has torn fins and nips. I caught the pyramid and put him back into the mini-QT tank inside the display tank.

My question is, can I do anything more to help the new addition be successful? Also, how long is it "ok" for the pyramid to be housed in that mini-DT? It's only got enough space for him to turn around comfortably but no real swimming is possible.
 
It seems as if the aggression is worse at night or when the lights are off. But yeah, the rearrange of the rocks thing could help. Man, I don't know if I want to do that though. I would have to break encrusted SPS corals across the rock work.
 
How large is the tank? Desjardini tangs can be very aggressive, and, in my experience, once they start down that path they only get worse.
 
You can try removing the tang for a while (a week maybe) to let the butterfly settle in and then reintroduce the tang later.
 
How large is the tank? Desjardini tangs can be very aggressive, and, in my experience, once they start down that path they only get worse.

That, and size of pyramid, desjardini, etc. I recently added four pyramids to my display, with a few resident tangs (including a Desjardini) but the pyramids are all of decent size (approx. 3 inches) and the sailfin is quite small.
 
isolation tanks and qt are very different...

eggcrate in the tank to seperate them for a while, rearranging all the rock and keeping in dark for a min of 3 days...can also put some mirrors on the sails side to keep her preoccupied...
good luck...
 
From what I'm reading, this is a reef tank. Just be careful with the lights out if you have any clams. I did lights out for 3 days, and my clam never recovered...
 
Fish aggression to new addition question.

Thanks everyone. Appreciate the input. Lots of good ideas. It might be possible to egg crate off a small side for the butterfly. That would be *much* easier than moving around rock work. It's an SPS tank and honestly the corals would only suffer (ie breaking them, bad new placement).

Anyway, yes 90g system with 25 gallon active water sump (35 gallon total volume). Minimum rock work with all sides open (no rock touches glass). I know sailfin will need to be housed in larger aquarium, but I was a noob when I started 1 year ago.

Sailfin is about 5" now.
Yellow Pyramid is about 3" but is also not as big around yet.

Other fish include:
2 small chromis'
1 peppermint hogfish
1 pajama cardinal
1 green mandarin
1 cleaner shrimp

The mini-QT tank I have as a small pump to keep water moving through the unit so water quality should be good, but will the size of it (small) eventually stress the fish negatively? How long can the pyramid be in there? (Also note I have a fully cycled 20g QT tank that the pyramid was just in for nearly 6 weeks so moving back in there is sort of an option, but that doesn't help introduction to DT).

Here's the size...
ha6apaga.jpg
 
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I have had two Desjardini tangs. Both were perfect citizens until the time they decided to be terrors. I thought I just had bad luck with the first one. After the second time, I decided it wasn't a matter of if, but when.
 
I think it might be time to re-home the sailfin. Which I know stinks, but on the other hand you could upgrade to a 180 and I have a feeling it would calm down. Fish can show environmental stress as aggression.

I have a clownfish that I got back in 2001 and she was a terror. Both my wife and I hated her, though not as much as she hated my wife. When move into the 125g from a 46g there has been no further aggression.
 
Just wanted to report that I was able to introduce the butterfly while keeping the sailfin "entertained" long enough for the butterfly to figure out a spot in the rocks to live and how to deal with the sailfin coming near him.

1. I left the pyramid in the mini-QT tank (pictured above) for 8 additional days. I think it was getting hard for him to live in there any longer.
2. During this time I attached the sailfins nori to the front of the mini-QT box so they got a lot of face time. Not sure if this helped but I did it.
3. On the day of the release I added multiple sections of egg crate into the tank too kinda of simulate rock work rearrangement. This helped a lot.
4. I taped mirrors to one side of the tank along with blank cd's. The mirrors definitely attracted the sailfin tang.
5. I suction cupped PVC to the inside of the glass. This made the sailfin tang weary of going to various spots in the tank.
6. I over feed the tank everyday twice.

The added items were in the tank for 3 days. A couple are still in the tank. Anyway, since the pyramids introduction he has only got one additional fin nip, and that was on day 1. As of now, the sailfin hasn't showed him any more aggression than he does any other fish in the tank (ie an occasional 1-2 sec chase that results in the tang swimming in the opposite direction).

Well, so far so good. Glad I got to keep the yellow pyramid butterfly! They are one of my favorite fish that I've been literally trying to get for like 9 months. Even had one previously that died in QT. They seem to be very hard to find and acclimate, but my current one is a champ. Very healthy.
 
Sounds like you scared/confused the heck outta that tang lol. I have a tomini that doesn't always like new comers and a mirror usually distracts him long enough to get over them :)
 
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