Holy!; Severely Torn Fins?!

[FishHelper101]

Wow i'm in a state of shock and panic! Here's what happened:
Ok so as usual everyday I check my 10 gallon sorority for anything unusual. So when I went to check on Devena (one of the female bettas) a HUGE piece of her fin was missing! I'm thinking it's Roxy! (The "boss" betta) She has no damaged fins and seems to be fine! Devena is having trouble swimming because of the lack of ya know fin!! What should I do??? I know I didn't tell you guys I stalked it because I haven't had time! To busy setting up (I'm so sorry!) Anyway here's the stats and the tank updates:
 
Nitrate- 0
Nitrite- 0
Water Hardness- 150
Chlorine- 0
Alkalinity- 40ish
pH- 7.8
Ammonia- 0ppm 
 
10 gallon currently stalked with:
-3 female bettas (1 female died the first night (She didn't look too good anyway R.I.P Toto <3)
 
Decor:
-4 plants (all artificial)
Crittertrail tubes (yes for small animals!)
and a ceramic yellow duck (Used to be my hamster's house but it was cleaned)
 
Hopefully this proves no problems >,< Thanks guys!

 

[techen]

Ceramic yellow duck is what I want.

Treat with melafix and wait for it to grow back really.

 

[Zikofski]

haha techen will do anything for that ceramic yellow duck , and yes agree with techen with melafix, just keep an eye on infection fingers crossed it wont, i have the same with a few of my barbs but i am not treating it just keeping the tank clean and over time it should heal, just note can you keep betta's in the same tank together? i may be wrong but i thought they had to be separate

 

[the_lock_man]

just note can you keep betta's in the same tank together? i may be wrong but i thought they had to be separate

 
So long as they're all females, it's not usually a problem.

 

[Zikofski]

ah sweet learnt something new

 

[FishHelper101]

Ah ok! I have melafix that I used for my male betta! Thanks so much and nuu my yellow duck xD Thanks guys

 

[RCA]

....
10 gallon currently stalked with:
-3 female bettas (1 female died the first night (She didn't look too good anyway

R.I.P Toto <3)
 
Decor:
-4 plants (all artificial)
Crittertrail tubes (yes for small animals!)
and a ceramic yellow duck (Used to be my hamster's house but it was cleaned)
....

 
A couple of things stand out for me:
1. you really need more than three female fighters to prevent any aggression towards any one fish.  With female Bettas I have been advised by breeders that it is the only time you should overstock, as this prevents the aggression.
2. Your plants etc.  When you say all artificial are they plastic or silk?  Have you tried the stocking test?  i.e. run a nylon stocking over all the items in your tank to make sure that nothing can shred the Bettas tail?  If the stocking gets snagged the Bettas tail will also.
 
Of course, the reason you state could well be the cause, just some other pointers that may assist further issues.
 
Just another thought, is there anything else in your aquarium other than the three Bettas?
 
Are you able to load a picture of Devena, and of course the duck?  
Do you have a picture of your aquarium on the forum?

 

[FishHelper101]

....
10 gallon currently stalked with:
-3 female bettas (1 female died the first night (She didn't look too good anyway

R.I.P Toto <3)
 
Decor:
-4 plants (all artificial)
Crittertrail tubes (yes for small animals!)
and a ceramic yellow duck (Used to be my hamster's house but it was cleaned)
....

 
A couple of things stand out for me:
1. you really need more than three female fighters to prevent any aggression towards any one fish.  With female Bettas I have been advised by breeders that it is the only time you should overstock, as this prevents the aggression.
2. Your plants etc.  When you say all artificial are they plastic or silk?  Have you tried the stocking test?  i.e. run a nylon stocking over all the items in your tank to make sure that nothing can shred the Bettas tail?  If the stocking gets snagged the Bettas tail will also.
 
Of course, the reason you state could well be the cause, just some other pointers that may assist further issues.
 
Just another thought, is there anything else in your aquarium other than the three Bettas?
 
Are you able to load a picture of Devena, and of course the duck?  
Do you have a picture of your aquarium on the forum?

I know but Trixie was separated and toto died I started with 5…
They are plastic and yes I did no rips or snaps
Yes I have a picture but I don't know if it's still up i'll post one tomorrow
I'll upload Devena and the duck tomorrow as well 

 

[RCA]

I tend to stay away from plastic as these are more likely to cause damage.  Most of my aquariums have real plants, with a few of the boys having silk, as there is not enough light for real plants.  If you have done the "rips and snaps" and all was well then I guess they must be pretty soft plastic.
 
Just keep their water ultra clean and if you can add IAL (Indian Almond Leaves) if you have not already.
 
Look forward to the pictures.

 

[FishHelper101]