Sick Neon Tetras

[midnight23]

I have a planted 20 long with a Betta, Snails, and 8 Neons. I just noticed that my neons all have a dark brown stripe under their red stripe, one is very pale/losing it's color.



I know they lose their color when they sleep, but it doesn't seem right during the day. The Betta is healthy other than a few tears in his tail(he plays chicken with the filter intake).​

 

[Earlybird]

Has the tank cycled? Have you tested the water? Neon's tend to be a little
sensitive to changes in water perameters, especially in non-established tanks.

 

[midnight23]

Yes my tank is cycled, it's been so for over 8 months. I test my water every week, it's always 0 for everything, nitrates are usually low. My temp hasn't changed either, always 79.

 

[Earlybird]

How long have the neon's been in the rank?

 

[midnight23]

Around 6 months, I introduced the snails 3 months ago, but that shouldn't make much of a difference? They're nerites.