Brown Bugs

[jrbray]

Any one know what this bug is? I have lost two fish in 24 hours that were eating previously. When I removed them there were swarms of a brown fast moving bug, about the size of a pin head. I have tried searching for brown bugs on dead fish but can't find any photos detail enough. This one isn't detailed but hopefully with my description will help.

Thanks

 

[ThRoewer]

What fish was that?
Did the fish had bugs on them before they died or did they only show up after they died?

From what I can see of that fish in the picture it was seriously undernourished.

 

[jrbray]

It was a Ignitus Anthias, I got four about a week ago and the others do not appear to have the bugs on them.