How to tell when aggression needs an intervention

[adittam]

I added a new fish to our tank last night, a small (a little less than 3” long) male Melanarus wrasse. Current inhabitants of the 46g tank are a two spot bristletooth tang, a bicolor blenny, and a small pair of clowns (80g upgrade is finally in my possession, so it’s coming soon!). The tang is about 3” long and the king of the tank. I’ve noticed the tang chasing the new Melanarus intermittently, so I’m curious how much of that is ok, and at what point do I need to do something to intervene? I did not use an acclimation box, but I did introduce the wrasse when only blue lights were on last night, about a hour before lights out. The wrasse was out and about for about 45 minutes last night, then dove under the sand for the night, and has been out and about again today since the lights came on at 9:30. The wrasse has been eating all day, so I’m not currently worried, but more looking to learn what to watch for in the future.

 

[kittenbritches]

I don't have a tang, but do have a foxface and melanurus wrasse together and they are best friends. They zoom around together and hide next to each other in caves.

Your tang might just be trying to flex with a new "big" guy on his turf.

 

[adittam]

I don't have a tang, but do have a foxface and melanurus wrasse together and they are best friends. They zoom around together and hide next to each other in caves.

Your tang might just be trying to flex with a new "big" guy on his turf.

That’s exactly what I think he’s doing, but I don’t have any experience with two bigger fish in the same tank, so I’m just making sure I don’t miss anything.

 

[vetteguy53081]

When there is damage and it leads to injury or death - Time to isolate or evict the culprit

 

[adittam]

When there is damage and it leads to injury or death - Time to isolate or evict the culprit

Totally agree. Any advice on how to stop it a step before that happens?

 

[kittenbritches]

Totally agree. Any advice on how to stop it a step before that happens?

If you start seeing nipped fins or distress.

 

[vetteguy53081]

Totally agree. Any advice on how to stop it a step before that happens?

Try the mirror trick - tape a mirror to an area where the fish favors and it will direct its attention to the new IMAGINARY fish

 

[i cant think]

I added a new fish to our tank last night, a small (a little less than 3” long) male Melanarus wrasse. Current inhabitants of the 46g tank are a two spot bristletooth tang, a bicolor blenny, and a small pair of clowns (80g upgrade is finally in my possession, so it’s coming soon!). The tang is about 3” long and the king of the tank. I’ve noticed the tang chasing the new Melanarus intermittently, so I’m curious how much of that is ok, and at what point do I need to do something to intervene? I did not use an acclimation box, but I did introduce the wrasse when only blue lights were on last night, about a hour before lights out. The wrasse was out and about for about 45 minutes last night, then dove under the sand for the night, and has been out and about again today since the lights came on at 9:30. The wrasse has been eating all day, so I’m not currently worried, but more looking to learn what to watch for in the future.

As others have said, nipped fins, injury or the point of death are signs of this however what is the first initial signs? Elongated amounts of chasing, if the chasing goes on for over 4-5 days then you know to intervene. The tang seems to be stressed aswell (Usually that species are a darker brown and the yellow tail is not that light). Mine is about 2 inch and not that light which is what makes me think it’s not a juvenile coloration.

To me, that behaviour is for sure normal. It’ll stop within a few days (If not hours), mine acts like that with any newcomers! I just leave it for a few hours, feed them and come back to see no aggression but I’ve been lucky with every fish that is classed as aggressive - My Scott’s wrasse shows no care in the other wrasse in my tank, my Jade Wrasse is also a very peaceful fish and doesn’t attack anything (Shes 4” so at the size they tend to get destructive at that size).

 

[adittam]

As others have said, nipped fins, injury or the point of death are signs of this however what is the first initial signs? Elongated amounts of chasing, if the chasing goes on for over 4-5 days then you know to intervene. The tang seems to be stressed aswell (Usually that species are a darker brown and the yellow tail is not that light). Mine is about 2 inch and not that light which is what makes me think it’s not a juvenile coloration.

To me, that behaviour is for sure normal. It’ll stop within a few days (If not hours), mine acts like that with any newcomers! I just leave it for a few hours, feed them and come back to see no aggression but I’ve been lucky with every fish that is classed as aggressive - My Scott’s wrasse shows no care in the other wrasse in my tank, my Jade Wrasse is also a very peaceful fish and doesn’t attack anything (Shes 4” so at the size they tend to get destructive at that size).

EXACTLY the type of info I was looking for. Thank you!

 

[JumboShrimp]

My take on that video— it will sort itself out within the next few days. (Moving around one or two rocks significantly so your Tang’s favorite spot has been disrupted could speed things up; he’d have to find a new personal ‘territory.’)

 

[i cant think]

As others have said, nipped fins, injury or the point of death are signs of this however what is the first initial signs? Elongated amounts of chasing, if the chasing goes on for over 4-5 days then you know to intervene. The tang seems to be stressed aswell (Usually that species are a darker brown and the yellow tail is not that light). Mine is about 2 inch and not that light which is what makes me think it’s not a juvenile coloration.

To me, that behaviour is for sure normal. It’ll stop within a few days (If not hours), mine acts like that with any newcomers! I just leave it for a few hours, feed them and come back to see no aggression but I’ve been lucky with every fish that is classed as aggressive - My Scott’s wrasse shows no care in the other wrasse in my tank, my Jade Wrasse is also a very peaceful fish and doesn’t attack anything (Shes 4” so at the size they tend to get destructive at that size).

I just realised I forgot to edit the “Stressed colouration” part - Those colours are just what they do to show dominance, similar to when wrasses flash are other wrasse.

 

[nereefpat]

Nothing in that video is worrisome at all.

What would worry me:
1. Slashing with the caudal spine, especially any damage
2. If the wrasse is chased into the sand and doesn't come out to eat.