worwood worwood
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  • Posted on: 5/1/2012 13:01
Aggressive fin-nipping #1
Hey everyone ? it?s been a while!

I have a problem - has anyone ever experienced an aggressive fin-nipping goldie? My boyfriend decided to surprise me with a new goldfish a couple of months ago and this [insert expletives] fish is driving me insane with what seems like really aggressive and premeditated fin-nipping.

When I say she?s fin-nipping it?s more like ripping-to-shreds ? you?ve all probably seen goldies shred plant leaves off now replace that plant with a tail and that?s what she does. She?s already effectively killed one of the fish (who got a bacterial infection as a result of the fin-nipping and never recovered) and the other goldie got velvet as a result of the stress.

Water quality ? ammonia 0, nitrite 0, nitrate <10
dosing - 10ml easycarbo every day, 10ml TPN+ once a week
Feeding ? twice a day, varied between: tetrafin gold japan, Tera Natura Algae Mix, Tetra Natura Bloodworm mix, frozen spinach, frozen brine shrimp, frozen bloodworm and the occasional peas and courgette and broccoli and excess Salvinia natans from the tropical tank (when it threatens to take over)

This has been my train of thought about why she does it:
Boredom ? possible, but has plenty of plants and hiding places not sure what else to give them
Territory ? 240L fluval roma with 2 goldies <4 inches long? doubtful
mating behavior - well she?s female and he?s male so it?s the wrong way round and as I explain above this is ripping of tail not a slight nibble
Hunger ? I used to just feed once a day but noticed they were getting a bit lethargic with the strongish flow in the tank so have upped it to twice a day
Mistaking tail for floaty-plants ? possible but even when the fish swims off she actively chases them to start the nipping again

I?m at my wits end and was about to take her back to the LFS after seeing my other goldie?s tail torn to shreds again but boyfriend made me feel guilty so now I?m off to buy a tank divider so she can live in isolation before she kills the other one

Argh any ideas?
suey2 suey2
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  • Posted on: 5/1/2012 20:16
Re: Aggressive fin-nipping #2
Hmm, naughty newbie fish! I have had a bullying female before, she was a pearlscale so fortunately wasn't capable of doing much damage as she could rarely catch anyone but if she did corner someone she would have quite a go and never passed up the chance for a nip if someone came too close to her I'm afraid I never resolved her behaviour, she had a big tank, lots of tank mates, plants etc. so I don't think she was bored, I just think she was a bit of a rotter! She died quite young though so I didn't have to think about dealing with her long term A couple of the younger males used to nip an older, less active one but was able to sort that by separating them to different tanks and they don't bother the fish they are with now

Is the newbie smaller than the older fish?

Brigitte has recently done a blog on making a tank divider which might be worth a nosey for a temporary measure
It's Not Just A Fish
worwood worwood
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  • Posted on: 6/1/2012 12:49
Re: Aggressive fin-nipping #3
Yep, Newbie is about a third of the size of the older fish.

I don't think it's food related either as she's too preoccupied with food to fight. I wish older fish would have a go back to teach her a lesson but not sure that's going to happen as he seems scared of her now.

looks like tank divide is the only immediate solution anyway; as i don't have room for another tank and can't keep a goldie long term in the 40L quarantine tank and above all i need to give older fish's fins time to heal again
suey2 suey2
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  • Posted on: 8/1/2012 0:37
Re: Aggressive fin-nipping #4
Hmm, tricky one It's possible she'd be better behaved with a larger tank and a bigger group of livelier fish to 'dilute' her behaviour and give her a run for her money but that's not really much help to you. Maybe try the tank divider for a while and then once original fish is better try them again It's something of a long shot but you could try intervening every time you catch her nipping, goldies do have a concept of cause and effect so if she associates nipping with a hand coming in and pushing her away (I don't mean give her a slap, just push her away from him! ) there's a vague possibility she might get the hint. But that is a long shot!
It's Not Just A Fish
worwood worwood
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  • Posted on: 9/1/2012 13:41
Re: Aggressive fin-nipping #5
Haha i now have an image me of slapping a fish round the face in my head - it's all a bit too tempting given the circumstances! But in all honesty I don't think i'm around enough during the day enough to be consistent with any behaviour-training.

I was considering adding more fish - i'd probably comfortably get another 2 goldies in the tank providing i keep on top of water changes - but i'm just worried she'll attack any new comers as well since she's already 'killed' one.

Have ordered my bit-and-pieces to make the tank divide so i'll stick to that for now.