Neon Tetras: Can't figure out what they have

[Laser]

First off, the remaining 15 neons are kept in an established 20 high. I perform a weekly water change of 50%. The current paramaters are 0,0,20.


It starts off with a slight white discoloration near their tail fin, but still on their bodies. It gradually grows larger over the course of about 2 weeks. They eat and shoal normally until finally they become deformed and die. I have a video I have taken since I can't get any good pictures. I've full rounds of treatments with Maracyn 1 and 2 as well as kanamycin to no avail. I'm thinking about trying Furan 2.

Part of me wonders if these neons are just merely genetically weak due to the way they are mass bred. I have no evidence to support this, but the neons die slowly one by one.

It may be hard to see the white spaces near their tail or cuadal fin, but this was the best I could get.

DSCI0297 - YouTube

 

[spiketooth]

Same thing happend to me, got 15 of them and 5 died with no reason. I would say its the way they are breeded. Keep with the normal schedule and everything. Could add stress coat, see if that helps then out,

 

[Helix]

Part of me wonders if these neons are just merely genetically weak due to the way they are mass bred. I have no evidence to support this, but the neons die slowly one by one.

I recently bought 15 neons as well and they have the same thing... never again will i get neons, they just seem sickly. I found so many posts about neons with illness. Mine started with ich as soon as i got them home, one had a bit of tail rot. Treated for a fews days at high temp and lots of water changes, ich disappeared and tail rot improved. Then two days ago I noticed this white patch/discoloration on one of them, mid and tail sections. Now another one has it. I'm trying to treat them but I'm afraid it's only a matter of time.

 

[Laser]

A lot of times people are quick to say it's NTD, but as I said it's not characteristic of NTD. The legions don't begin in the same places and they don't look the same.