How to identify cyanide caught fish?

[Reeffer]

seems to me that one of my fishes is cyanide caught.. fins seems to be degenerating.. and developing pop eye after it has started eating.

[ciaolong]

Cyanide breaks down enzymatic systems that metabolise oxygen in the blood. Eventually it means that oxygen won't reach the liver, heart, brain, and other organs of the fish. Basically they suffocate from the inside. The most obvious symptons are heavy/fast respiration and lethargy.

In addition to the symptoms , I've been told "brighter than usual" coloration on fish could be an indication of cyanide poisoning. For example, flame angels should be a more ruddy orange-ish color, not bright red. I'm not sure how the cyanide alters the color, if this is true, unless it has something to do with blood/oxygen flow in the fish because the liver is damaged.