glass knifefish laying on bottom of the tank unable to swim

[Coryking]

I don't know whats happened my glass knifefish. I came in the morning and just found her laying at the bottom of the tank, not moving. I've moved her into a fish breeder box as i don't want the other fish bothering her. she is moving her ribbon fin and her pectrol fin, but is unable to swim. She was perfectly fine yesterday and even started hand feeding just a few days ago, so I have no clue what's happened to her. Is there anything I can do to try and save her? So far I've done a 50% water change, I've tried to feed her but she wouldn't take the food.

 

[GaryE]

How long have you had her, and what other fish are in the tank? She appears very thin, even for a species that has that look.

 

[Coryking]

Thank you for the reply. I've had her for about five months.
Her tank mates are 3 glass catfish, haraquin rasboras, 3 endlers one angelfish, corydoras, a flash pleco, a banjo catfish and a ninja wood cat.
I've always been target feeding her however as previously stated she has started to hand feed.

 

[GaryE]

I can think of nothing to suggest. It isn't the easiest fish to keep, and fish are like us, prone to sudden unexpected physical breakdowns. Heart attacks, aneurisms - they're part of being human, and fish have the same weak points.

Assuming your water quality is good, and the fish has been eating well, that shouldn't be an assemblage to cause trouble unless the tank is too small. Sometimes, things happen.