Betta Pelvic Fin Problem

[rockbellab]

Hi. I purchased two twin tail Betta's from a reputable online site two weeks ago. One is in a 20 long with some Cory Cats and doing great. Two days ago when I started feeding all the fish I noticed that the Betta in the ten gallon (tank with divider, a male Betta on each side) pelvic fins were gone and the area looked swollen/bloated where they were supposed to be. He had exhibited no signs of being unhealthy until that day. He is still eating well, swimming around normally and interacting with the Betta on the other side of the divider. Could he have gotten hung up on something and pulled the pelvic fins off and that is why he is swollen? There are medium sized river rocks (no sharp edges) and a medium sized Roman Coliseum (from the fish section). It is possible he could have gotten under is or something. What should I do? Could it be a disease or just an accident? I wasn't sure what to do so I've been adding Melafix and aquarium salt as directed on the packages. If I should be doing something else please tell me. I don't want him to die, he is such a cute little guy.
Tests are also great:
pH - 6.8
Ammonia - Oppm
Nitrite - 0ppm
Nitrate - 10ppm
Thanks for the help.
Bridget

 

[Rosemary]

Hi Bridget,

I'm sorry your betta isn't feeling well. It sounds to me more like an injury than finrot if only the pelvic fins are affected.

Are there any plastic plants in the tank? I found out the hard way that plastic plants can tear a betta's fins . Does the Colisseum have any rough edges? Unfortunately sometimes things sold in the fish section do have rough spots which can tear a betta's fins.

Can you find the torn off fins in the tank?

Poor little guy, I hope he heals quickly.

 

[rockbellab]

Thanks for replying. I took all the plants out before I got this Betta but the Coliseum did have rough/sharp edges so I took it out today and put in something rounder that he will be less likely to hurt himself on. I vacuumed the tank and found what seemed to be pieces of the fins. You helped me feel calmer. Thanks.