Close Menu
    Facebook Instagram
    Facebook Instagram
    MyAquariumMyAquarium
    • Home
    • News
    • Posts
      • Freshwater Aquarium
      • Marine Aquarium
      • Disease
        • Bacterial Disease
        • Parasites
        • Protozoan
    • Fish Species
      • Freshwater Fish Tank
      • Saltwater Fish Tank
    • Invertebrates
    • Plants
      • Low-Tech Plants
      • High-tech Plants
    • Inglês
      • Português
    MyAquariumMyAquarium
    Home»Posts»Freshwater Aquarium»10 Reasons Why Your Fish May Be Dying
    Freshwater Aquarium

    10 Reasons Why Your Fish May Be Dying

    Adriano GolobBy Adriano Golob06/06/2020Updated:06/06/20201 Comment7 Mins Read
    Facebook Twitter Pinterest Telegram WhatsApp
    10 Reasons Why Your Fish May Be Dying porque-meus-peixes-estao-morrendo

    Why are my fish dying? Is there anything I can do? In this article we will cover 10 reasons why your fish may be dying.

    We all ask ourselves: Why are my fish dying? In the world, the life expectancy of a fish that leaves a petshop store is generally no more than 3 – 4 weeks. Certainly, many of them die in a few days, or even in a few hours. Fish are the most badly treated pets in the world.

    Certainly, fish are more fragile animals than we are, but that does not mean that they should live for a short time in an fish tank. Most early deaths are due to some mistakes that we can identify and avoid.

    Next, we will discuss the 10 most common mistakes that may be killing your fish.

    Índice

    Toggle
    • Lack Of Use Of Water Conditioners
    • Incorrect Temperature For The Species
    • Death From Lack Of Oxygen
    • Tank Too Small For Your Fish
    • Fish Overfeed
    • Sudden Changes In Temperature, pH And Water Hardness
    • Ammonia Poisoning Because The Fish Tank Has No Filter
    • You Have Not Cycled The Fish Tank
    • Fish Died Of Disease And Parasites
    • Do Not Perform Partial Water Changes Frequently

    Lack Of Use Of Water Conditioners

    Tap water is perfectly good for any fish tank, as long as you have used a good water conditioner to remove heavy metals. However, without the conditioner, chlorine and chloramine in tap water can kill fish.

    See Also:

    • Why Do My Fish Stay On The Surface Of The Fish Tank?

    How to solve it: Just purchase a good water conditioner for tank. Certainly, they will be available in every pet shop store. A single conditioner can last a long time. And its operation is almost instantaneous, when added to the tap water.

    Incorrect Temperature For The Species

    Most tropical fish come from warm waters ranging from 21°C to 26°C in temperature. In summary, the water in your fish tank may not be at the ideal temperature, depending on the region in which you reside. Since most of the fish sold in the petshop are from tropical waters, they may experience sudden changes in temperature.

    How to solve it: Get a heater or thermostat to leave in the fish tank, or the fish can acquire diseases and die in a short time.

    Death From Lack Of Oxygen

    Your fish need oxygen dissolved in the water. However, they can die if that dissolved oxygen runs out. Several factors can cause this to happen:

    1 – The fish tank may be too small for the species. Less water means less dissolved oxygen;
    2 – Overcrowding the tank with fish. The more fish you have, the more dissolved oxygen your aquarium will need;
    3 – High temperatures. The higher the temperature of the fish tank, the less dissolved oxygen;
    4 – Lack of pump / air filter.

    See Also:

    • How To Solve Oxygenation Problems Of The Fish Tank?

    How to solve it: Get a pump or filter with the ideal capacity for your fish tank. This will increase the rate of gas exchange between water and the atmosphere.

    Tank Too Small For Your Fish

    A small tank has very little water. This means very little dissolved oxygen, as mentioned earlier. Unfortunately, small tanks mean unstable temperature, water hardness and pH.

    Dirt also accumulates more quickly. Without a doubt, some people still keep fish in small bowls and cups. None of which is suitable for keeping animals

    See Also:

    • Fish Bowls! Why Are They Bad For Fish?

    How to solve it: We do not recommend anything less than 18 liters for a small betta fish, for example. The bigger the fish tank, the easier it will be to keep the fish alive.

    Fish Overfeed

    Overfeeding fish can cause digestive problems and kill animals very quickly. This excess causes “pollution” in the aquarium water and an increase in toxic substances such as Ammonia and Nitrite, which are also fatal.

    See Also:

    • Why Is My Fish Spitting Out The Food?

    How to solve it: Feed the fish only once or twice a day. Add a little feed in the water and check the animal’s behavior in the search for food. After a few minutes, it will no longer have the same behavior and you can stop feeding it. Any leftover feed must be removed immediately, as it can sink and rot, causing the problems described above.

    Sudden Changes In Temperature, pH And Water Hardness

    Fish are not like us, they have no body heat and are sensitive to sudden changes in water temperature. Water pH and hardness can also affect them if there is a sudden change.

    See Also:

    • What Is The Ideal Temperature For My Fish Tank?

    When we bring a fish home, after buying it from a store, it usually comes in small plastic bags. However, the water in this bag is more likely to be very different from the water in your fish tank. Simply “dumping” the fish in the water can kill it quickly. If they suffer any type of shock, they can die in a matter of hours or a few days. Anyway, most of the sudden deaths happen due to this reason.

    How to solve it: You need to “acclimatize” the fish slowly to allow the animal time to adapt to the new water.

    Ammonia Poisoning Because The Fish Tank Has No Filter

    Filters in aquariums are mandatory. Since they serve for biological filtration. Without this, the Nitrogen Cycle (Cycling) will never start. As a result, toxic ammonia will accumulate and kill your fish.

    The fish poop, along with leftover food, will rot and produce ammonia. This compound is toxic to animals. The ammonia concentration must always remain at 0 ppm, this is the only acceptable value.

    How to solve it: Buy a filter for the fish tank and purchase biological media. Remembering that the filter must stay on 24 hours a day, seven days a week.

    You Have Not Cycled The Fish Tank

    A new filter needs to be cycled to keep the ammonia and nitrite levels zero. This process takes about 4 – 6 weeks. During this time, ammonia and nitrite will accumulate. Both will increase and decrease over the weeks. However, most fish do not tolerate these compounds in the tank, so it is ideal that the aquarium does not have any animals during this period.

    How to solve it: Cycle before adding the fish.

    Fish Died Of Disease And Parasites

    There are hundreds, if not thousands, of parasites and fish diseases. For example, Dropsy, Ich, Lernaea and Popeye. Many of them are contagious. A single sick fish can cause everything else to die if not treated properly. Many people report that the fish started to die after introducing a new animal to the tank.

    How to solve it: Buy healthy animals from reliable sources. If you go to a store, check where the fish are stored, if there are no dead fish, or if they are showing some type of irregular swimming.

    See Also:

    • 10 Tips For Beginners In Fishkeeping;

    Isolate fish purchased in a quarantine tank for at least 3 weeks. You can also separate a diseased fish and place it in a separate aquarium. Treat the animal as quickly as possible with the products available on the petshop market.

    Do Not Perform Partial Water Changes Frequently

    Even if you have a perfectly cycled tank, the end product of the Nitrogen Cycle – Nitrate – will accumulate. Although this compound is relatively harmless, very high concentrations can affect the animal’s immune system in the long run.

    How to solve it: Perform partial changes of 30% – 50% once a week to keep nitrate levels under control and add some plants in the tank so that they can also consume this compound.

    What did you think of this article? Do you have questions about reasons why your fish may be dying? Leave it in the comments!

    Previous ArticleFish Disposal And Donation!
    Next Article Top 6 Benefits Of Plants in Fish Tank
    Adriano Golob

    Related Posts

    Top 50 Best Freshwater Aquarium Fish Species

    Top 50 Best Freshwater Aquarium Fish Species

    03/08/2023
    How to Set Up A Perfect Goldfish Tank

    How to Set Up A Perfect Goldfish Tank?

    27/01/2023
    Celestial Pearl Danio Galaxy Rasbora tank mates blog

    Top 10 Tank Mates For Celestial Pearl Danio

    23/01/2023

    1 Comment

    1. Pingback: Why Are My Fish Not Eating? How To Solve? - MyAquarium

    Leave A Reply Cancel Reply

    Posts Mais Lidos

    Top 50 Best Freshwater Aquarium Fish Species

    Top 50 Best Freshwater Aquarium Fish Species

    03/08/2023
    the most colorful freshwater fish for your aquarium

    10 Most Colorful Freshwater Fish For Your Aquarium

    16/01/2023
    Por que meu peixe Betta esta deitado no fundo do aquário capa Why My Betta Fish Stay at the Bottom of the Tank

    Why My Betta Fish Stay at the Bottom of the Tank?

    04/12/2021
    10 Best Fish to Put in a Small Fish Tank

    10 Best Fish to Put in a Small Fish Tank

    31/08/2022
    Facebook Instagram
    © 2025 MyAquarium. Todos os Direitos Reservados. Política de Privacidade.

    Type above and press Enter to search. Press Esc to cancel.