Help Me Figure Out What's Nipping My Fish's Fins!!

So, as most of you already know... I sold my 8 foot long breeder tanks, so I had to pretty much dump all the fish that were there, into my 100 gallon tank.

When the fish were in their separated "cubicles" they all seemed fine. Now that they're all sharing one tank, I've noticed that some of the fins on some fish have been nipped at. Even some, missing a good portion of their fins (CRAP!)

So, now I'm trying to figure out which could be the culprits... Here are the fish that are in the tank:

UNLIKELY Fin Nippers
- Mickey Mouse Platties x?? (too many to count)
- Albino Corydoras x6
- Sailfin Plecos x2
- Albino Bristlenose Plecos x6
- White Cloud Mountain Minnows x?? (too many to count)
- Striped Raphael Catfish x3
- Weather Loach x1
- Gardneri Killifish x2
- Golden Wonder Killifish x2
- Bullhead Catfish
- Black Neon Tetras x?? (too many to count)

Possible Fin Nippers
- Baby Kribensis x3 (well, they're more like juvies now)
- Black Skirt Tetras x4 (I know they need to be kept in a higher number, but they've been in the 100 gallon tank for a long time, and they haven't had any fin nipping issues before)
- Red Minor Serpae Tetra x6 (same as the Black Skirt Tetras)
- Bandula Barbs x9
- Odessa Barbs x?? (not sure how many there are...+6 for sure)
- Florida Flagfish x1
- Green Tiger Barb x1 (I thought it was this, but it looks like his fins have been nipped at as well)
- Xenotoca Eiseni Females x2 (These are the ones I'm mainly considering, that are nipping the fins out of EVERYONE)
- Emperor Gudgeon Females x3 (dunno if these are even THAT aggressive...)

I've currently taken out the two Xenotoca Eiseni females, in hopes that those are the fin nipping culprits, but I figured I'd ask some opinions from you all

Patties are notorious fin nippers (and can verify that personally). Black Skirts and Sepraes are both well known nippers as well. Not familiar with Bandula bards, tigers as you know are bad (but he obviously isn't nipping his own) ... not sure about odessa barbs though.

Huh... I was not aware that platties were fin nippers... Mind Blown.

Yeah, waaaaaaaay back in my first tank ... the did a pretty good barber impersonation on my dwarf gourami's and angelfish.

I'll second the platies as also nippers. Also WCMM will nip anything when they are competing for territory (petco calls them semi aggressive). And my clown killifish will also nip fins to compete, so maybe your killifish might too? And I don't have neon tetras, but my head and tail lights will get nippy if provoked.

I dunno man, to me it sounds like half your population in that tank is of the fin-nipping variety and the real problem is one of not enough hiding places. Could that be it? How densely planted is the tank? Are there beds of very thick plants where fish can go hide in?

Two possible things to try if you haven't already: Increase food, fat happy fish aren't as aggressive. At least there would be less competition for food. And plant some thicker foliage (a large and tall bunch of subwassertang, java fern, baby tears, guppy/star grass) so that the fish being nipped can go hide faster.

I agree with the platy comments. And then you have classic nippers...the larger to medium sized schooling tetras and barbs are notorious for nipping as its their nature and the way they "play" with one another. If they don't have have enough of their own to nip (and that would be lots really) they will nip others. I had a tiger barb as a kid...nastiest fish in the tank. My small tetras don't seem to have issues of nipping although I do see them messing with each other sometimes.

Because you have quite a mix of fish in your tank doing what you are doing will probably be the best way to find out who (and there may be multiple) the culprits are. Or you can reverse it and remove the ones being picked on...setting up another tank for the more docile fish...and leave the aggressors to duke it out. At some point it will become clear who is who but it may take a while.

Wholly freehollio, there are many species in there that could be nippn'....

Lots of goOd suggestions here,

What I would do to find the critter that's guilty; 1. Grab a beer and a chair and watch them for a while. 2. Weed them out by finding which fish DONT have nipped fins . 3. Species segregation - removing one species at a time.

Not than it would be a fin nipper, but wouldn't that bullhead be a threat in the tank with the small fish?

Betty: Oh yes. I've seen him gobble up some white clouds before. I got him when he was only about an inch long, and now he's a good 5-6 inches! I wouldn't mind it if he ate the other fish. LOL.

PokeSephiroth wrote:Betty: Oh yes. I've seen him gobble up some white clouds before. I got him when he was only about an inch long, and now he's a good 5-6 inches! :DI wouldn't mind it if he ate the other fish. LOL.

So fin nipping is NG, but wholesome fish eating is ok? I guess if you're gonna do something, you might as well go all the way!

How serious of a problem is the nipping though? Is it a very high % of fish getting nipped?

Mrtom: Hahaha yeah because wheb the yet eaten whole, they don't suffer as much as if their fins are getting nipped at. :p

Alas, I will be Getting rid of the xenotoca Eiseni, Odessa Barbs, Kribensis, and maybe the Tiger barb... Although, the Tiger barb has been schooling around with the bandula barbs because they look similar, so I'm sure that has reduced it's chances of nipping other fishes fins (although, I should know better than to trust a tiger barb. Hahaha)

As for feeding, I feed them twice a day, in the morning and at night, when I get home from work (when I work).

I'm going to continue and closely monitor the entire tank for now.

Seems like a good majority of the fish have nipped fins.

What to do with the platties... Hmm..

Uhh, frying pan, butter and platties equal hot poppers. LOL

So, I ended up getting rid of the Odessa Barbs, Xenotoca Eiseni, 2 Kribensis, Florida Flagfish, and a couple others. Hopefully that will lessen my "search" for trying to figure out who are the fin nippers.

I've yet to see any of the platties nipping any fins... it just can't be them. I REFUSE TO BELIEVE THAT THEY ARE THE CULPRITS!! . . . lol

 - Golden Wonder Killifish...

Hmm.. nope, those golden wonder killifish always stay at the surface, and never venture down to where the other fish like to hang out.

They may eat a white cloud here and there, but I don't particularly care if they eat the white clouds. =P

 - Hmmm