Tetra Problem

[bllackpython]

Well i didn't want to find myself in this thread but hey ho here we go again.
 
I have recently added plants and bogwood to my tank. They didn't all go in on one day I added them all over about 2 weeks. I had 6 tetras and 1 doctor fish who seemed happy enough.
 
This weekend gone I tested the water on the Friday (all was clear), did a partial water change on the Saturday and then went to get more fish on the Sunday.
 
I bought 6 Corys and 10 tetras (bringing me to 16 total).
 
All seemed OK but to be honest I was paying more attention to the Corys than the tetras!
 
Then I noticed on Monday that 1 tetra wasn't looking too good, he was swimming as normal but he had white on his body.
 
Today I have noticed he has gotten worse and his swimming has now been affected.
 
Here is a video of him:
 
http/s23.beta.photobucket.com/user/voldermort69/media/IMG_03031_zpsdee2e652.mp4.html
 
My main concern is that he will pass it to the other fish. Everyone else looks fine it's just him
 
*Update*
We have now put him in a small tank with no filter or heater but he's kind of just lying at the bottom, still alive.
I don't think he will make it... Do you think any of my other fish will catch what ever he had?

 

[bllackpython]

Any one have any ideas?

 

[PrairieSunflower]

I can only tell you my experience with Neons... for me, white patches has meant neon tetra disease (which is not curable and can spread)... after losing one per month I stopped waiting until I was "sure" and euthanized them the moment anything suspicious occurred and it seems to have stopped the problem.

 

[bllackpython]

Thanks for the reply.
 
That doesn't sound too nice but i guess it had to be done. I will keep an eye out but hopefully no one else will get it. I did remove the fish before the others realised he was weak.