Gills shrunk and fillaments gone??

[Kat1983]

Hi i have 2 axoltyls in the one tank in the last few weeks one has began to look sick, has gotton quite skinny.
His gills look shrunken and the fillaments have all but dissappeared. his skin doesnt look quite right either. He has not eaten for around 10 days several times he takes the food but spits it back out a few moments later.

The other one is healthy and eating well .

I have done a partial water change tried a salt bath a few days ago. he is simming better and looks a little healthier but still not eating and look quite skinny.

I have a 4 foot tank, filter, small air stone.

Thankyou for your help.

 

[Morrison]

What are the water parameters?
Do you have gravel in the tank?
Can you see anything abnormal on the gills? (Tiny worms, other beasties...)

 

[Kat1983]

No gravle in tak just spvery lrge river rocks.
Nothing abnormal on gills that i can see the fillaments are almost all gone.

He has been much more active in the last day and taking a lot more food. Still spitting most of it out moments later i have tried smaller portions...

What do you mean by parameters?

Thankyou