Why is my fish turning darker

    • Best Answer

    A lot of time fish will change color as they mature and age out. This can be slight changes, up to a full on color change (such as going from white/black coloration to gold for example).


    Other times they can change color due to them showing dominance in the fish (cichlids are known to do this as the most dominant fish will be a more unique color) or due to their gender (Auratus cichlids for example).

  • Sometimes this can be a HUGE change, although it normally happens through time. You might notice spots forming of different color, before a full transformation.


    Otherwise if it seems to be a gray coloration or another type (let’s say a Neon Tetra turning white) than it actually might be a disease vs. normal color changing.

  • How can you tell if it’s normal vs a disease or something? Like does fin rot turn pieces darker or some other diseases?

    Most diseases will end up either fraying the fins, or if it’s a color change, will either change to white (like a fuzzy white), red/pink (due to sores and blood), or black (dependent of its it’s a fungal issue). In almost all cases though, the behavior of the fish will have changed (hides more, eats less, less active, etc). Although color is a good sign of a disease, there are other aspects you can notice by simply watching that fish for a small period of time that would be more detailed and informative on what they may have.