Fish aggression - on again, off again?

ACBlinky · 07/27/2008, 11:41 PM

I have witnessed the strangest behaviour in the last few months, thought I'd ask if anyone has seen this or if there's an explanation for it.

I bought a Potter's wrasse, let her become established, and later bought an ornate/Christmas wrasse. For quite some time they just ignored each other and the tank was harmonious.

Then one day, the Potter's disappeared. I thought we'd lost her, but saw her before lights-on the next morning, swimming around as usual. The lights came on, the other wrasse emerged, and chased the Potter's into hiding. Any time the Potter's came out, the other wrasse dashed over and frightened her back into the sand - she never bit, but she chased the Potter's relentlessly. After a while I got into the habit of feeding the Potter's at around 6am, and lights-on became her new 'bedtime'.

I got pregnant, got quite sick, and was just not up to dismantling the tank to get the bully out. I tried traps, and caught everything but the intended fish. After three months of barely seeing one of my favourite fish, I finally felt well enough to do something. I was ready to try fishing her out with a hook & line and then...

Yesterday at lights-on, both wrasses were out swimming, ignoring each other. They ate breakfast together, stayed out all day, no conflict whatsoever. The same thing happened today. Did they have some sort of meeting, declare a truce? Can fish fight for months and suddenly just kiss and make up?

crvz · 07/28/2008, 08:25 AM

Maybe as they matured in age they made a truce. If one got large enough to defend itself, the other may have given up on their pursuit. Which christmas wrasse did you get? I think there are a few with that common name. Regardless, I've read that they're pretty peaceful, so here's hoping they've decided to become friends.

snorvich · 07/28/2008, 09:32 AM

It sometimes happens. It is almost like they forget that they want the other guy out.

It probably would not work with a Potters but I socially acclimate all fish in a acrylic breeder cup that has suction cups for the front of the tank. That way the new fish is protected while the existing fish get a chance to introduce themselves to their new roommate.

ACBlinky · 07/28/2008, 03:08 PM

Quote:

Originally posted by crvz
Maybe as they matured in age they made a truce. If one got large enough to defend itself, the other may have given up on their pursuit. Which christmas wrasse did you get? I think there are a few with that common name. Regardless, I've read that they're pretty peaceful, so here's hoping they've decided to become friends.

I should have given the Latin name, the ex-bully is Halichoeres ornatissimus. S/he is larger than the Potter's, though not by much. Neither have really grown in the past few months, if anything the Christmas wrasse has grown larger.

The two are getting along incredibly well now, I hope this continues! Thanks for your replies guys

07/27/2008, 11:41 PM	#1
ACBlinky Premium Member Join Date: May 2005 Location: Peterborough, ON, Canada Posts: 4,954 Blog Entries: 20	Fish aggression - on again, off again? I have witnessed the strangest behaviour in the last few months, thought I'd ask if anyone has seen this or if there's an explanation for it. I bought a Potter's wrasse, let her become established, and later bought an ornate/Christmas wrasse. For quite some time they just ignored each other and the tank was harmonious. Then one day, the Potter's disappeared. I thought we'd lost her, but saw her before lights-on the next morning, swimming around as usual. The lights came on, the other wrasse emerged, and chased the Potter's into hiding. Any time the Potter's came out, the other wrasse dashed over and frightened her back into the sand - she never bit, but she chased the Potter's relentlessly. After a while I got into the habit of feeding the Potter's at around 6am, and lights-on became her new 'bedtime'. I got pregnant, got quite sick, and was just not up to dismantling the tank to get the bully out. I tried traps, and caught everything but the intended fish. After three months of barely seeing one of my favourite fish, I finally felt well enough to do something. I was ready to try fishing her out with a hook & line and then... Yesterday at lights-on, both wrasses were out swimming, ignoring each other. They ate breakfast together, stayed out all day, no conflict whatsoever. The same thing happened today. Did they have some sort of meeting, declare a truce? Can fish fight for months and suddenly just kiss and make up? __________________ "The cure for anything is salt water: sweat, tears, or the sea." - Isak Dinesen Current Tank Info: 150g mixed reef, 30g sump/refugium, LED lighting, 100lbs LR, coral beauty, flame angel, blue & yellow tangs, gobies, damsels, 6-line wrasse, lawnmower blenny, dottyback, clown pair, rabbitfish, shrimp, crabs, CUC.

07/28/2008, 08:25 AM	#2
crvz Team RC Member Join Date: Jul 2005 Location: houstonia Posts: 7,989	Maybe as they matured in age they made a truce. If one got large enough to defend itself, the other may have given up on their pursuit. Which christmas wrasse did you get? I think there are a few with that common name. Regardless, I've read that they're pretty peaceful, so here's hoping they've decided to become friends. __________________ -Chris- You don't win friends with salad. "Look! They're trying to learn for free!" ... "Use your phony guns as clubs!" Current Tank Info: rectangluar? wet?

07/28/2008, 09:32 AM	#3
snorvich Team RC member Join Date: Aug 2005 Location: Outlander Posts: 40,953 Blog Entries: 46	It sometimes happens. It is almost like they forget that they want the other guy out. It probably would not work with a Potters but I socially acclimate all fish in a acrylic breeder cup that has suction cups for the front of the tank. That way the new fish is protected while the existing fish get a chance to introduce themselves to their new roommate. __________________ Warmest regards, ~Steve~