Guppy Health Checker

Interactive symptom guide

What is your guppy trying to tell you?

Pick the symptom you are seeing. The Health Checker will show what to check first, common non-diagnostic possibilities, and which part of the tank or care routine deserves attention next.

Choose the main symptom

Start broad

One symptom can have more than one cause.

The safest first step is usually to compare the fish's behavior with water quality, temperature, stocking, feeding, recent additions, and whether more than one fish is affected.

One fish affected

Look closely for injury, bullying, body changes, appetite changes, or an individual health problem.

Several fish affected

When multiple guppies change behavior at the same time, water quality, temperature, oxygenation, toxins, or a shared infectious problem deserve more attention.

Problem began after a change

New fish, a large cleaning, filter-media replacement, new décor, medication, or a temperature swing can provide an important clue.

Four checks that belong at the top of almost every health investigation

Water qualityCheck ammonia, nitrite, nitrate, and anything else relevant to the setup.
TemperatureLook for overheating, chilling, or rapid swings.
BreathingCompare normal gill movement with rapid or labored breathing.
Recent changesAsk what changed in the tank during the last several days.

Use the checker as a triage tool, not a diagnosis.

Many fish symptoms overlap. White marks, bloating, poor appetite, fin damage, and abnormal swimming can come from different causes, so avoid treating blindly based on one symptom alone.

  • Check the environment before assuming disease.
  • Look for combinations of symptoms.
  • Observe whether the problem is affecting one fish or the whole tank.
  • Quarantine can be useful when a new or clearly sick fish needs separate observation.
Next Care guides

Use the full guide that matches what you found.