What Makes a Fish Look Like It's Peeling?

For most fish, skin that appears to be peeling is a sign of disease or damage. However, for a handful of fish, like the marine parrotfish, peeling is perfectly normal. Know what "normal" looks like for your species before resorting to medical intervention.

  1. Fish Skin

    • The skin of most fish has several mechanisms to protect against disease and injury. Many but far from all fish have scales, which act as tiny pieces of armor to ward off injury. Additionally, most bony and lawless fish produce a thin layer of protective mucus to protect the skin from parasites. Damage to the scales and problems with the mucus can give a fish the appearance that the skin is peeling. These conditions may require treatment.

    Parrotfish

    • For parrotfish, peeling skin doesn't necessarily mean disease. At night, parrotfish produce extra skin mucus, forming a cocoon to protect them from parasites while they sleep. The mucus also has a bitter taste that deters predators. Extra skin slime can easily give the appearance that a fish is shedding skin. However, this is normal for these fish.

    Physical Damage

    • Fish may lose scales from physical damage. For example, many species of fish may lose a few scales if they have a fight. Often this will go hand-in-hand with minor damage to the fins, particularly splitting along the fin rays. You may need to separate the combatants to prevent further injury. Usually, with minor injuries like this, you just need to sit back and let the fish heal after separating the feuders. Unless you see signs of secondary infections, like fuzzy patches on the injuries or red streaks, just keep the water clean and the fish well-fed and they should heal on their own.

    Slime Disease

    • Fish skin can look like it's peeling in the instance of slime disease. In slime disease, parasites infect the fish's skin, and the fish produces excess skin to try and dislodge the parasites. The fish may rub against aquarium decorations, trying to dislodge the parasites. Many pet shops sell topical remedies for this ailment. It's usually a good idea to treat the entire aquarium since these parasites can spread.