Why is my fish acting so strangely?

[dawngleason]

I have a 100 gallon FOWLR tank, and have had a Flame Angel and a Clown Trigger in it for about 6 weeks. They're my only fish so far. The Trigger has been fine all this time. He ate well from day one, has been fearless, will let us hand feed him and even pet him.

For the past two days, the Trigger has been acting very strangely. He spends most of his awake time swimming up and down on one end of the tank, nipping at the glass from time to time. Tonight, he has been doing this almost non-stop for over five hours. He also darts away every time someone approaches the tank. He has never done this before, and, in fact, always rushed to the front when we approached (looking to be fed, I'm sure). He is still eating well, by the way.

I put a Lion Fish in the tank two days ago, so I'm wondering if this new addition could be causing my Trigger to become stressed. The two fish aren't really paying any attention to each other, but that's the only thing that has changed since the Trigger started acting like this.

All fish were quarantined for 4 weeks before going into the big tank. Amonia, nitrate and nitrite are at 0. Ph is 8.3, salinity 2.5, temperature 80 degrees.

Any ideas or suggestions?

[dawngleason]

Apparently, no one here knows. :)

[petoonia]

How big is the trigger? Is the tank only 4 feet long? Is it still eating well? Any other unusual behaviour

[dawngleason]

The trigger is about 3" long, and the tank is 5 feet long. The trigger is still eating well, and, other than what I mentioned in my first post, is not doing anything else unusual. He looks great, with no loss of color, fin damage, etc.

[RedEyeElf]

fish are like people, sometimes you just get an oddball:)

is there anything shiny near the tank?

I've seen fish ramming the side of a tank when there was 2 acrylic tanks side by side

[alan214]

I'd be willing to bet that adding the Lionfish is what has the Trigger upset. He'll get used to his new tankmate in no time.

[dawngleason]

There's nothing shiny near the tank. There is another glass tank next to the big tank, but it's at the opposite end of where the trigger is doing his compulsive, constant up and down swimming.

I realize fish will just sometimes act oddly, but this is new behavior for this trigger. He has been fine for ten weeks, and has just gone "crazy" since I put the lion in with him.

Also, he's not ramming the side of the tank, just nipping at it from time to time.

[petoonia]

After reading your post again it reminded me of something. I've seen my Coral Beauty show aggresion to her reflection in the glass. Sounds like your trigger might be seeing its reflection, and it isnt too happy about another trigger in its tank. LOL

[dawngleason]

<a href=showthread.php?s=&postid=9120998#post9120998 target=_blank>Originally posted</a> by petoonia
After reading your post again it reminded me of something. I've seen my Coral Beauty show aggresion to her reflection in the glass. Sounds like your trigger might be seeing its reflection, and it isnt too happy about another trigger in its tank. LOL

LOL! Yes, I've seen him do this from time to time before, just not for hours at a time. He's such a little pig when it comes to eating, and I joke that he wants to get rid of that "other trigger" before he eats all the food! :D

Thanks to the poster that said my trigger should get used to the lion soon. I love my trigger dearly, and would do whatever I could to make him happy. But I also think the lion is way cool, so I'd hate to have to give him up.

[dawngleason]

By the way, I do tend to call the really colorful, beautiful fish "her", and the fish that look like the trigger and lion "him". Call me sexist. :)