Whose Chewing On My Corys?!

[brianna5691]

i noticed earlier today that there are a couple bites missing out of my two smallest albino corys' dorsal fins. i have 1 blue gourami(3 spotted), 3 albino cory cats and 4 zebra danios (3 of them glofish and one regular red). and also 2 zebra snails. ive noticed over time my danios are oddly aggressive towards each other, unless they're playing. I personally think they look like they're chasing and biting at each other but maybe thats how fish play, idk? ive heard that blue gouramis can be kind of aggressive. both danios and gouramis are fin nibblers. but cory cats dont even have gorgeous long fins, they're kinda short and stubby. who ever it is seems to be picking on my smallest cory the most he/she is about 1 1/2in. btw its a 20 gal tank. can someone tell me whose the most likely nibbler??

 

[onidrase]

both gouramis and danios can be aggressive. Danios are definitely fin nippers, and I've noticed they tend to be nippier in smaller spaces like a 20 gallon. three spot gouramis in general can be nasty fish. I've never been able to keep one without it trying to kill others when it reaches the 4-5 inch mark.

 

[brianna5691]

hmmm, well knowing that. i think i should probably get rid of some. i just asked someone if they would want my danios, so i have wait for a response. i think taking those 4 fish out may help. they're constantly chasing each other. the corys always mind their own business and the gourami is honestly the same. she did eat my angelfish so im not ruling her out but shes usually timid. my gourami is about 4in, so maybe. im going to try to remove the danios and see if things improve. thanks for your imput

 

[creeker]

Are you sure it's not Fin Rot on your Cories? It's a pretty common bacterial disease. Cories usually stay under the radar of fish like that, that is, they usually get ignored.

 

[snazy]

Corys are the easist target for fin nippers.

 

[brianna5691]

im pretty sure the fins have been nipped because ive had fish with fin rot before. does quite look the same and also because i noticed two nibble marks left the house for about 3 hrs came back and it looked like at least 7 or 8 nibble marks. as far as i kno fin rot isnt that quick. and since i noticed the first two bites, the nibble marks look the same. my friend is going to take my danios in couple days i think my corys should be fine for now.

is there anything specific i should put in the water to help mend his fins faster? ive just been using stress coat when i do water changes. any ideas?

 

[creeker]

Just keep the water clean. You don't want to dump any unnecessary chemicals in there

 

[N0body Of The Goat]

My money would be on the Danios, because when kept in small numbers, they are far more spiteful than when kept in groups of 8 or so.

 

[chrisjd]

I was going to buy 5 danios to put in my 25 gallon tomorrow, I suppose I should reconsider now I don't want my pygmy cories to get nipped.