How To Tell If Guppies Are Stressed?

Guppies can experience stress as well. Many sicknesses and diseases are caused by stress in guppies. But how to tell if guppies are stressed? What are the signs of stress? Here’s everything you need to know.

Stress in Fish

How To Tell If Guppies Are Stressed Stress in fish, including guppy fish, is caused when fish are kept in improper conditions. Although guppies are a very strong and highly adaptable fish, there are still many cases when they are not able to adapt to their environment, in this case with the aquarium. Stress decreases the fish’s ability to fend off diseases and it can also impede the fish’s ability to heal itself in case of injuries. Guppies that are stressed also experience a loss of appetite and infertility. Not only that, but stress can also reduce the lifespan of your guppies as it can lead to an early death.

Top Causes of Stress in Guppies

  • Low water temperature.
  • Small or overcrowded tank.
  • Aggressive tank mates.
  • Poor water condition.

Low Water Temperature

Tropical fish like guppies prefer warm waters. Temperatures between 65-85 °F (18-30 °C) are the norm. It’s best to use a water heater to keep the temperature stable. Anywhere between 75-78 °F (24-26 °C) is ideal.

Tank Size

Keep guppy fry in about 0.5-1 US gallons (2-4 liters) of water volume per fish. Female guppies can grow up to 2 inches in length and males are about 1.2 inches. You can safely keep 6-7 guppies in a 10-gallon aquarium.
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Never overcrowd a tank. While most types of guppies are peaceful, fish can become territorial and will fight each other for dominance. This leads to increased stress within the community.

Tank Mates

As mentioned, guppies are peaceful. If an aggressive fish attack a guppy, it won’t fight back. Hence, not all fish make good guppy tank mates. For example, certain species of betta fish should never share a tank with guppies. Angelfish, barbs, or any fish big enough to eat guppies should be avoided.

Water Conditions

Here are few things to consider when setting up a guppy fish tank with regard to the water conditions of the aquarium.
  • The ideal water temperature for them is between 75-78 °F (24-26 °C).
  • Temperatures below 74 °F (23 °C) increase the chances of guppies getting sick.
  • Temperatures above 86 °F (30 °C) decrease the oxygen. Eventually, oxygen is depleted and fish die due to asphyxia.
  • The water pH level also affects guppy fish.
  • Keep your guppies in water with pH level between 7 and 8.
  • Use a water conditioner to remove chlorine, chloramine, and heavy metals if you plan to use tap water.
  • Cycle your aquarium before introducing your guppies.
  • Add live plants to your aquarium to help reduce nitrates.
  • Use an aquarium filter to keep ammonia and nitrites at 0 ppm and nitrates less than 20 ppm.

Symptom of Stress

  • Guppy fish lose their appetite and eventually refuse to eat when stressed.
  • Guppy fish hide continuously or sink to the bottom of the tank.
  • Stressed guppies lose some of their colors and become pale.
  • Guppies dwell near the surface gasping for air.
  • Nipped fins or injuries on their bodies.
  • Cloudy or swollen eyes (this can be caused by bacteria or internal parasites).
  • Female guppies get extremely thin after giving birth (caused by stress during labor).
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Stress leads to several health issues in the guppy community. Identifying the cause of stress and addressing it accordingly and as soon as possible is a must. When treating illnesses using medication, turn off UV sterilizer and remove the active carbon from your filter as these neutralize the medication. Keep your guppies with non-aggressive fish. Feed them. Perform weekly water changes and maintain your fish tank regularly. Maintain proper heating. That’s about it when it comes to keeping you guppies happy. Resources:

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