Deformed Fry?

[Merebere]

About a month ago one of my swordtails had babies! I was so excited! I have a fairly basic community tank, and I "let nature take its course" so I didn't set up any breeding nets or anything like that. I was devastated when I witnessed almost every single fry get eaten by it's parents when I turned off the light in the evening. But to my surprise, about 2 weeks after I thought they had all died, I saw 1 fry! It had grown to about 15mm!! But after watching it, it seems to be deformed! Its still alive, and can easily swim away from the other fish. It's tail doesn't look developed, almost like it has something over it.. its very strange... It can eat, and swim... should I be worried about this? I was thinking about putting it in it's own tank so it can grow stronger, and then re-introduce it into the community tank again, would this be a wise idea?
Thanks

 

[Merebere]

I tried to take a video of the fish, but I have a pretty low-quality camera.. but here it is

[URL="http/www.youtube.com/watch?v=E6nnZHPjIao"]http/www.youtube.com/watch?v=E6nnZHPjIao[/URL]

the video isn't so great, but it kinda shows the crazy way of swimming this fish has...
- it kinda looks like it is eating, but there is no food.. thats just how it swims... werid..

 

[Merebere]

A new development!

For the past few days I haven't seen the little fish, but then I saw it today, and it seems to have shed its weird tail thing... anyone ever seen anything like this? or know what this could be?

 

[LauraFrog]

I posted to say that I didn't know what it was but my post didn't display!

I looked at the video but I couldn't really see anything abnormal. I've had bent fry straighten out and grow into normal fish, there's a fair chance that it will fix itself naturally.

One clear, side-on photo would be useful if the deformity is still there.