Infection?

  • We are currently upgrading MFK. thanks! -neo
Really sorry to hear that - I would treat the tank for sure since you know you had an infected ray that died. The female may be strong now to fight off the infection, but if she becomes stressed she could succumb to it as well.
 
Might be chloramines, I've noticed when it's present it will cause them to shed their slime coat and die

If you're using prime it wouldn't show on a test kit or if your kit is out dated.

Sodium chloride at 1tbsp/5gal has always helped. Not only does it help the fish but it helps to reduce the toxicity of the spike
sent via homing pigeon.
 
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