Why Do My Guppies Have White Spots?

White spot in guppies is a disease called (Ich or Ichthyophthirius multifiliis). This is a parasitic disease that is widespread among aquarium fish. This disease starts when a parasite called protozoan finds its way to the fish gills, body and fins then attacks those parts.

Why Do My Guppies Have White Spots? If you see white spots on your guppies this means they have parasites on the skin, the white spots usually look like crystalline sugar or pinch of salt. The symptoms start with difficulty in breathing, then they have issues moving from one place to the other, and you might later flush them down the drain due to death.

Why Do My Guppies Have White Spots

Ichthyophthirius multifiliis popularly called white spot can wipe all your aquarium fish within days if urgent steps to isolate infected guppy is not taken. However, you need the help of a veterinary doctor to stand a chance of controlling the proliferation in your aquarium once a fish is infected because it is contagious.

Signs Your Guppy White Spot is Deadly

Below are the traits you will notice if this protozoan is around your aquarium.

  • Once the parasite gets pass the fish protective mucous membrane, the guppy starts scratching its body against decorative items in the aquarium.
  • Prominent among fish with white spot is upside-down swimming
  • Fins clamped against the body.

These white spots are tiny; they are like the size of a pinhead, the spots can be seen at the initial stage when the fish is placed under a fluorescent light though they can be seen around the gills because they are first infected.

Gold spot wrasse

In addition, you know once the gill is affected, there will be a difficulty for them to breathe. The periorbital tissues which hold the eyes muscle are struck, and you will witness the fish having protruding eyeball.


The Lifecycle of the Protozoan.


The biological cycle of protozoan is distintive when in a free form, you will notice it feed and reproduce from the host tissue. The development of the parasite is in different stages, and it gets to the eyes, fins, skin of the host at the infecting stage. After this stage, it gets entirely into the body, leaving microcirculatory lesions that can only be seen under a microscope.

After this stage, it gets to the epithelial cells, which is a point of no return because the immune system is encased here. This biological reaction can take place within 24 to 48 hours, the entire process is epithelial hyperplasia after which the white spots are produced, within 30 days over 2,000 new parasites can be produced in the fish.

Why Guppies Have the White Spot

The main reason why guppies contact white spots is a sudden change in water temperature; imagine replacing water at 30 F to the fresh ones at 20 F. Fish that have acclimatized with the temperature will be affected.

Polluted aquarium environment is the foundation of almost all diseases an aquarium fish will face, and the white spot is not an exception because of the parasite breeds in unkept tanks.

The third reason is the introduction of parasite cysts carrying live plants or decorations to the aquarium.


Preventing deadly parasite is possible. Keep the aquarium clean, have a consistent temperature/PH level even when freshwater is introduced, sterilize plants with disinfectant, boil decorative items and stones before placing them in your tank.


Hello, I'm Jason. I'm the guy behind HelpUsFish.com. I volunteer at my local fish shop and I created this site to offer tips and advice on the fish I care for.

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