Fins been nipped

[OscarRomeoFiveTwo]

Noticed that one of my bronze Cory's fins has been completely nipped off and a few others also been nipped.( Tiger barbs the main culprits) not seen them yet nipped but

Do the fins grow back?

 

[AdoraBelle Dearheart]

Yes, fins can grow back, however, there are a few big problems, looking at that fish in the photo.

Firstly, any damage to the fins leaves the fish vulnerable to secondary infections from bacteria and/or fungus that are always present in our tanks. Stressed fish are even more vulnerable to secondary infections, and that fish is incredibly pale, quite skinny, and is showing every sign of severe stress and feeling very unwell and unhappy.

The fins have also not just been 'nipped', they've been bitten right back to the body, so much higher risk of secondary infection and death. Can also see the larger bronze cory to the right has had their dorsal fin shredded too.

Firstly, the cories need to be moved to a hospital quarantine tank as soon as possible. That one isn't just missing fins, it's very stressed and sickly looking, and cannot recover while in the same tank with the aggressors. Tiger barbs are notorious for nipping and aggression, especially if not in the right group number to disperse that among themselves, but what else is stocked in the tank? Could also be another culprit.

If you don't have a hospital tank, then a temporary one can be rigged up using a large food safe storage tote and rigging filtration and a heater (not against the plastic itself, resting on stones or similar). We can talk you through how to get some set up quickly in an emergency like this.

The cories, and especially that skinny pale one in the centre, need to be rescued since they can't escape the glass box themselves, and are being eaten alive. They need very fresh, clean water, zero ammonia/nitrites, and nitrates as low as possible - fresh clean water boosts the immune system and reduces the amount of infectious agents in the hospital tank/tote. So frequent large water changes, and may well need further treatment if they develop a fungal or bacterial infection, so close observation, potentially an aquarium salt treatment (although cories can be sensitive to salt, so would need need to watch them when adding some diluted aquarium salt to see if they freak out. If they do, then immediately do a large water change to dilute out the salt. There's a guide to how to treat with salt (has anti-fungal and antibacterial properties, most fish can handle it for short term treatment, less likely to harm than many chemical meds, and a lot of products sold in stores are snake oil).

Alternatively, eSHa 2000 is a good product for problems like this, I've used it in the past.

 

[MaloK]

Tiger barbs are little jerks, adding them to a peaceful community, is like adding a bikers gang in a peaceful town.

They will act perfectly normal when you are there and start fighting and bullying a soon you turn your back. If you spy on them without them seeing you, you'll have your proof soon enough.

In large numbers, you can see they are constantly harassing each other. If a fish get weaker then the others. He will be targeted like no ones business. They are also notorious gills nippers. and try to suffocate their victim by destroying their gills.

Many peoples in the hobby say that you can have them with, Mollies, Pictus, Platties, Swordtails Cories etc...

I do not... If I would find one of my cory looking like that in my tank. I would be mad as hell. I really like them but always refrained to get some, because I Like the slower peaceful kind of finned frenzies and these guys they really need fast paced tank mates.

Your little buddy has lost all his means to escape the aggression with his fins gone. And will be the easiest target. I would remove all the barbs from the tank and relocate them. To give back a much needed calm environment for him, I never punish the victim. But I would gladly use a kakivac to remove the aggressor if needed.

One of the worst example I saw is a seasoned aquarist that writes articles on fish keeping for many years now.

Telling peoples you can keep them with cories with no problems. While showing a Picture of a Cory with nipped fins and tail.

 

[AdoraBelle Dearheart]

While I agree with most of your post, this part;

Your little buddy has lost all his means to escape the aggression with his fins gone. And will be the easiest target. I would remove all the barbs from the tank and relocate them. To give back a much needed calm environment for him, I never punish the victim. But I would gladly use a kakivac to remove the aggressor if needed.

It's not about punishing the victim - I say move the cories to a hospital tank because that cory especially is in a life-threatening emergency situation right now, and moving him (with his cory friends) to a clean fresh container that's more sterile will reduce the chances of infection, make it easier (and cheaper) to medicate, rather than medicating the main tank, and a hospital tank/clean new storage tote isn't going to be harbouring all the nasty bacteria and fungi that the main tank and it's gravel substrate has. He needs lifesaving attention first, then s/he can worry about finding someone or somewhere else for the tiger barbs while the cories are in intensive care, so to speak.

Also without knowing anything else about OP's tank besides their suspicions about it being the tiger barbs, which yes, can be brutal - without knowing the other stocking, there might well be more than one culprit finishing off what the barbs started, or vice versa. If they also have a red-tailed shark or something attacking the cories, then removing the barbs isn't going to solve the issue. Even generally peaceful fish will often target, peck at, and generally be horribly aggressive and mean to a sickly and dying fish, even if they were happily part of the same school previously.

I haven't looked for scientific backing for this theory yet, but I've witnessed and heard about it happening enough times to know how it's a known thing, and I suspect it's a survival instinct, just as has been observed in countless wild animal species. Weak, sick, vulnerable animals in the wild attract predators. It's why most animals hide visible signs of pain for as long as possible. Once hungry predators arrive, attracted by the scent/motions/chemical signals from the sick animal, all of the others are now also at risk too.

It makes sense to drive the sickly one away, in the hope that the rest of the group can escape downriver. When that happens in the wild, the sickly one then has the chance to hide, and potentially recover, depending on what ails them. Or they get eaten, and the circle of life continues. But in a tank where the others are trying to bully and peck at the fish acting like a beacon for predators to drive it away, it can't escape. Another reason is to prevent the remaining fish from eating the body of the sick one if it does pass away, just in case the illness was something infectious.

So hospital tanks aren't about punishments, just emergency medical care. Once the cories are out of the main tank and safe, and being medically treated, even if that's just with a clean environment and water, then the main tank should be assessed for suitability for cories, taking the whole stocking plus gravel into account.

 

[OscarRomeoFiveTwo]

Thanks for the comprehensive replies.

I don't have a hospital take to separate the Cory's but I do have a breader box I can uae for the time being. If nothing else but to stop him being eaten alive.


Been keeping a keen eye today and it is deffo the barbs, . The other fish seem fine it's just the Cory's that's been nipped.

 

[Byron]

The only solution is to remove the tiger barbs. Otherwise when they finish on the cories, they will look elsewhere. I don't know how many fish you have, but TB cannot (or should not) be in a shoal less than 12+, and if this is the case they need a 30g (minimum 30-inch) base. Beyond this they can be with some other fish. But numbers do make a difference with shoaling fish, and this one in particular.