Black "stuff" on Rummy Noses

[Giant]

Hi,

Just observed that a few of my Rummy Noses have got some black smudges on them.
They are quite small, affecting between 2 up to 6 scales.
They look kinda of like when u are doing some manual work & then get some grease on your skin that kind of smudges.
The fish don't seem to be behaving oddly.
Sorry, they just move about too fast to get a pi.

So just wondering if this is the start of a bacterial infection or something like that.

[benny]

This is suppose to be resulting from bacterial infection. The black marks are the fish's reaction from the infection. It's not suppose to infect other fishes nor will it pass on to the next generation. You can see this on dwarf cichlids too.

Cheers,