Pale and inactive bronze Cory catfish

[Harryg00]

One of my bronze Cory cats has suddenly gone very pale and just lays at the bottom rarely moving in the past week or so but all of the other fish in the tank look good and healthy any suggestions on how I could the help the fish?
In my tank there are:
4 bronze Cory cats
1 guppy (getting a couple more soon)
5 neon tetras
2 amano shrimp
And the tank is 54 litres.

 

[jonny-5]

Ive noticed the Corys are on gravel, They need sand. Gravel wears down the barbels which can get infected.
Corys normally only go pale in times of stress.
10G seems a bit small for the amount of fish, Any idea what your tank stats are?

 

[Harryg00]

Corys normally only go pale in times of stress.
10G seems a bit small for the amount of fish, Any idea what your tank stats are?

I did a water change yesterday but the stats are 0 ammonia, 0 nitrite and 10 nitrate

 

[jonny-5]

Sorry i had not finished editing my first post, Kids mithering at this time of night/morning

 

[Harryg00]

Sorry i had not finiahed editing my first post, Kids mithering at this time of night/morning

No worries, and I’m thinking of investing in some sand soon for them but I’m not sure as to why this one has suddenly gone pale I’ve even got a smaller juvenile Cory that hatched from an egg in the tank that is doing fine so not sure what’s wrong with the pale one.

 

[jonny-5]

How long have you had the fish in question?

 

[Harryg00]

How long have you had the fish in question?

I’ve had it for just over a year now