Help ,

[Kippalopsy]

My two black Corys have turned a silver colour over night , are they sick . They are still active and eating . What do I do .

 

[Colin_T]

Pictures and video of the fish?
What is the ammonia, nitrite, nitrate and pH of the tank water?

If they went pale first thing in the morning after the lights came on, then they produced a stressed colour pattern when the lights came on.

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TURNING LIGHTS ON AND OFF

Stress from tank lights coming on when the room is dark can be an issue. Fish don't have eyelids and don't tolerate going from complete dark to bright light (or vice versa) instantly.

In the morning open the curtains or turn the room light on at least 30 minutes (or more) before turning the tank light on. This will reduce the stress on the fish and they won't go from a dark tank to a bright tank instantly.

At night turn the room light on and then turn the tank light off. Wait at least 30 minutes (or more) before turning the room light out. This allows the fish to settle down for the night instead of going from a brightly lit tank to complete darkness instantly.

Try to have the lights on at the same time each day.

 

[Kippalopsy]

Pictures and video of the fish?
What is the ammonia, nitrite, nitrate and pH of the tank water?

If they went pale first thing in the morning after the lights came on, then they produced a stressed colour pattern when the lights came on.

---------------------
TURNING LIGHTS ON AND OFF

Stress from tank lights coming on when the room is dark can be an issue. Fish don't have eyelids and don't tolerate going from complete dark to bright light (or vice versa) instantly.

In the morning open the curtains or turn the room light on at least 30 minutes (or more) before turning the tank light on. This will reduce the stress on the fish and they won't go from a dark tank to a bright tank instantly.

At night turn the room light on and then turn the tank light off. Wait at least 30 minutes (or more) before turning the room light out. This allows the fish to settle down for the night instead of going from a brightly lit tank to complete darkness instantly.

Try to have the lights on at the same time each day.

Thankyou so much . As the days gone on one has gone back to black and the other is getting there . I think that could have been the problem . It’s something I’ve never heard of but will do now in the future .