Are there health risks to leaving a dead fish in the aquarium?

  • Sometimes one fish dies, without any apparent disease. In previous aquariums I would always remove them as fast as I could.

    Now my aquarium is a bit bigger, and I have some laziness to remove those bodies: they are too deep, or in the back, or partially eaten. So I decide to leave some, and they tend to disappear in a few days.

    Are there any safety issues by doing that? Will other fish die if they eat dead fish? Will they develop some mad fish disease?

    Sometimes, after you have established an aquarium, with everything working as it should, fish might die simply because it gets old, or have a shorter life-span due to its condition before being sold to you, or because some other fish had a fight with it.

    If only one fish died, without white / black spots, no sign of fungus or parasites, no alteration in the gills, I usually rule out diseases or environmental problems.

    We recently had a guppy die a couple days after we bought it, yet we never found the body. We do have small pond snails and the ammonia levels were 0, so I assume the snails cleaned it up. I try to remove a dead fish immediately. I have no idea how long it would take after it's death to toxify the aquarium. I really would like to know. I assume the size of a fish might have something to do with it.

  • Beofett

    Beofett Correct answer

    8 years ago

    Assuming you're absolutely certain that the fish did not die from a disease or parasite (I'm not certain how you would ensure that, short of having absolutely nothing new introduced into the environment for an extended period of time prior to the death)...

    I would say it depends upon what died, and the other denizens of your aquarium.

    If you have a decent Clean Up Crew that will rather quickly consume the body, you're probably not going to run any serious risks of the body releasing enough toxins to jeopardize the other fish.

    If you lack sufficiently voracious cleaners, or your dead fish is on the largish side, you should pull it out of your tank sooner rather than later, though.

    Generally, at least among saltwater tank owners, leaving a dead fish for the CUC doesn't seem that uncommon.

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Content dated before 7/24/2021 11:53 AM