What is this on my knife?

[snoopy65]

I asked this in diseases but no one has answered. I was hoping to put him in my tank with my severums but am afraid to until I know. Thank you for your help. http://www.monsterfishkeepers.com/forums/showthread.php?t=220950

 

[benzjamin13]

I'm pretty sure it's not contagious. Looks like a sore or a tumor. Treat it with higher temperatures and a bit of salt.

 

[Pyramid_Party]

Can even try some antibiotics

 

[Finalfire9]

Do you have any sharp stuff in your tank looks like scratch

 

[snoopy65]

No but one of the rd or the gt could have done it. Thanks for the help guys.