Fish Aggression, Will it Get Better?

[Jack22]

I added a flame angel to my tank tonight after the lights went out and immediately my rusty angel that was already in the tank started chasing the flame around the tank and nipping at him. He wouldn't let him go anywhere. I have a 120 with only 4 fish, 5 now with the flame, so there should be plenty of room for everyone. Both have been in tanks with other angels before. Unfortunately, due to the way the QT worked out, the rusty has been in the tank for about a month pretty much by himself. Just a square spot anthias and 2 clowns that keep to themselves.

Should I give it a few days to see if things settle out and they get along or should I just try to get one of them out ASAP?

Thanks.

 

[JumboShrimp]

I’m interested to see what others say. Is it a balancing test— waiting it out to see whether the aggression will abate before the fish gets beat to the point of death?

 

[Gareth elliott]

Could try removing one, and placing in an acclimation box. But no guarantee will work every dwarf has its own temperament.

 

[Jesterrace]

Not really surprised. Generally speaking you need to venture into the 6 foot long tank range to have long term success of mixing dwarf angels and add them at the same time. Once a dwarf is established in a 4 foot long tank it's tough to add another. My CB in my 90 gallon has been well behaved, but the moment I stick a mirror near the tank it attacks it's reflection mercilessly. I might try putting a picture/vid of another dwarf angel near the tank just to see if it has the same reaction. As mentioned they could settle in together with time, but only time will tell. Here is how my CB responds to it's reflection:

 

[cracker]

Maybe separate the ank with eggcrate. ight have to move some rock one on each side for a couple weeks .Migh twork might not .
as Jester says every fish has it's own personality. If you remove one take out the rowdy one & let the new one settle in.

 

[mort]

I always used to separate dwarf angels at the shop but a friend would put them together without many issues. I think the reason for success is it was temporary, they went in at the same time and their were really any decorations for territories to be established.
Adding them the way you have its tough to see things improving quickly. If you added the new one in a acclimation box it may have smoothed things a little but adding them together would have been easier. Some times its works in your sized tank but sometimes it's ww3. I'd watch them and as soon as you see damage step in. A tank divider might help smooth the transition.

 

[Jesterrace]

I always used to separate dwarf angels at the shop but a friend would put them together without many issues. I think the reason for success is it was temporary, they went in at the same time and their were really any decorations for territories to be established.
Adding them the way you have its tough to see things improving quickly. If you added the new one in a acclimation box it may have smoothed things a little but adding them together would have been easier. Some times its works in your sized tank but sometimes it's ww3. I'd watch them and as soon as you see damage step in. A tank divider might help smooth the transition.

Agreed. I had my Coral Beauty and Yellow Tang in the same holding tank at my LFS for 2-3 weeks with no problems, I acclimated them both for a few days and added them to the tank at the same time. For a month they shared a cave together and hung out together. Then I noticed a chunk missing from my Coral Beauty's lower fin and some white injury marks on it. Then I noticed the Yellow Tang following the CB around and shadowing it's every move through the rockwork and it started backing up and slapping it with it's tail scalpel (the source of the white injury marks). Out the Tang went and the issues with the CB have disappeared and it has healed nicely. Thankfully my Coral Beauty has proven to be super resilient (ie been through ich, a traumatic transfer from the LFS, the aforementioned issues with the Yellow Tang)

 

[Jack22]

Thanks for the advice everyone. I’ll keep a close eye on it for a few days.

I’m going to probably have to get a fish trap if I need to get the rusty out. Too many corals to take the rocks all apart try to get him with a net.

 

[Jesterrace]

Thanks for the advice everyone. I’ll keep a close eye on it for a few days.

I’m going to probably have to get a fish trap if I need to get the rusty out. Too many corals to take the rocks all apart try to get him with a net.

If your rusty is still relatively small, you can easily make one out of a disposable bottled water bottle (I prefer them to soda bottles due to potential residual issues from soda bottles). I used the following method to trap my jerk of a Flame Angel who was about 3 inches AND an aggressive Red Head Salon Fairy Wrasse:

A 20oz plastic water bottle, cut the top off and fold the top inwards in a sort of funnel. Get a couple of small rocks/substrate from the bottom of your tank and put it in the bottom of the bottle to weigh it down and put some pellet food or it's food of choice in the bottom of the bottle (I find pellet seems to work best for trap purposes because it sinks when it gets wet) and then stand it vertically on the bottom of your tank. This makes it so the fish has to do a vertical U-Turn to attempt to get out. Then simply wait for the fish to inspect it and swim down in and reach down cover the top and pull up (or you can poke a couple of holes in the bottle near the top and have some fishing line running to the top, but you will need to stand there and wait, which will be a pain).

If you prefer something more like an actual trap, Sea Side Aquatics makes a couple (a smaller one that is 3x3x5 and one that is 4x4x6). The smaller one is $41 from Amazon and the larger one is $50 from the same place. I have the smaller one and did a review of it here:

 

[norfolkgarden]

This one has a heavy glass door and has caught 7 different fish over a 2 year time as fish have grown too aggressive.

I keep a mostly calm tank now.
[emoji849]

Drill a hole further back and just feed frozen inside it for several days without the tube and without worrying about catching anything.

Works like a charm for aggressive fish on the 3rd or fourth day.

If you are trying to catch the beat up fish the fish isn't likely going to near it. Too afraid.
[emoji53]

 

[norfolkgarden]

Um, adding the photo helps...

 

[Silence]

I have a 120 gallon tank, with lots of rock caves, and places to swim. The established coral beauty chased the newly added flame angel, whenever the flame angel swam close by, but I kept them together, and fed them a lot of nori, and frozen foods, so they are well fed. After a month or so, the aggression stopped. They are not friends, but are not enemies. 2 Tangs, 2 dwarf angels.. Lots of Nori.

 

[MnFish1]

Dwarf angels as a rule dont get along well = but give it a couple days. If not - return it. Dont try to divide, acclimate, etc IMHO - it doesn't work. Unless you have a really high density of fish in a tank 2 dwarf angels is likely to be a problem

 

[ca1ore]

Definately give it a few days. Chasing and nipping is often benign; but if one starts cowering in the corner or shows open wounds removal is necessary.

 

[DJF]

I have had great luck with the mirror trick when introducing new tangs or angels to the crew. I get a lg mirror and stand it on one side of the tank- first on the opposite side of where I release the newbie (after acclimation box). That preoccupies the bully with themselves while the newbie can get the lay of the land... then I will set the mirror where the bully sees themselves while also seeing the newbie. This keeps them preoccupied while seeing and glancing over at the new fish. Eventually they feel like the other fish has been there all along and as long as they aren’t the intimidating reflection fish then they are not a threat. There’s still some posturing after the mirror is taken down but by then the newbie has the lay of the land and can use the rockwork to their advantage. If you have an extremely over aggressive fish then make sure you don’t wear them down too much with the mirror and give them some breaks from the stress of their reflection. Watch other fish too to make sure no one gets over-obsessed. Also feeding more helps to alleviate aggression. As to how long to leave the mirror up- your call based on how the bully handles life & it’s new partner in between reflection bouts. There’s plenty of examples online & one of the best tips I’ve received from a fellow reefer.

 

[Jesterrace]

This one has a heavy glass door and has caught 7 different fish over a 2 year time as fish have grown too aggressive.

I keep a mostly calm tank now.
[emoji849]

Drill a hole further back and just feed frozen inside it for several days without the tube and without worrying about catching anything.

Works like a charm for aggressive fish on the 3rd or fourth day.

If you are trying to catch the beat up fish the fish isn't likely going to near it. Too afraid.
[emoji53]

Funny you should mention that, I use a similar method with my trap. I leave it with the door off for a few days and let the aggressive fish get comfy with feeding from it and then I add the door just off center so it stays up. Then I wait for the fish to swim in and be distracted by feeding and I simply tap the door and it slams shut and the fish is trapped. I used this method with an aggressive snowflake ocellaris and my Yellow Tang. Much better than standing there with fishing line waiting to pull a pin out.

 

[ca1ore]

Um, adding the photo helps...

I've used this trap with good success; recently for a purple tang that was attempting to shred my gem.

 

[MnFish1]

I've used this trap with good success; recently for a purple tang that was attempting to shred my gem.

I was going insane trying to catch a lemon peel angel - left the trap in for a couple days, door open. etc etc - the fish would never go into it when I was holding the string - finally put some rocks around the 3 sides and the top - it went in within 2 minutes.

 

[ca1ore]

I was going insane trying to catch a lemon peel angel - left the trap in for a couple days, door open. etc etc - the fish would never go into it when I was holding the string - finally put some rocks around the 3 sides and the top - it went in within 2 minutes.

Very good! Always nice when one can outsmart the fish …… rather than the other way around LOL.

 

[Jack22]

Dwarf angels as a rule dont get along well = but give it a couple days. If not - return it. Dont try to divide, acclimate, etc IMHO - it doesn't work. Unless you have a really high density of fish in a tank 2 dwarf angels is likely to be a problem

I actually QT 4 fish all together. Flame angel was just the first that I added to the tank. I still have a yellow tang, sailfin, and small Watanabe Angel that I will be adding over the next few weeks. I'm hoping the addition of all those new fish, especially the yellow tang since he is a little aggressive too, will calm the rusty down.

It's been two days. Flame angel did find a safe place to hide from rusty. He only comes out to eat right now. Maybe just a little more time and the other new fish will work it out.