Âge approximatif: 1 ans – 9 ans

The adult goldfish stage

Between 1 and 9 years, goldfish enjoy long, social adult years. A large aquarium, strong filtration, regular water changes and measured feeding are the foundation of this stage.

  1. Jeune
  2. Adulte
  3. Senior
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En bref

  • Adult goldfish need a large aquarium with strong filtration, or a suitable pond.
  • Regular water tests and partial water changes are the most important routine.
  • Overfeeding spoils the water; feed measured amounts.
  • Fancy goldfish can be more sensitive when it comes to swimming and balance.
  • Plants and chances to forage provide enrichment.

Adulthood runs from about 1 to 9 years of age. Goldfish can live a long time in good conditions, and this is the stage where a solid care routine is kept up for years.

What is happening in this stage?

  • Growth slows but may continue; size depends on tank and care conditions.
  • Colors can change over time.
  • They may recognize you and come to the front of the tank at feeding time.

What should you do differently?

  • Aquarium: A large, strongly filtered and well-aerated setup sized for the group.
  • Diet: Goldfish food varied now and then with suitable vegetables and frozen foods, only as much as they eat in a few minutes.
  • Water quality: Regular partial water changes, and don't rinse filter media under tap water, to protect the cycle.
  • Enrichment: Hardy plants, open swimming space and chances to forage on the bottom.

What should you monitor?

  • Water values (ammonia, nitrite, nitrate)
  • Appetite, swimming and balance
  • Fins, scales and eyes
  • Chasing within the group

Expected behavior

Sifting the substrate, waiting at the surface for food, cruising as a group and chasing during breeding season can all be seen at this stage.

Reminders

  • Weekly partial water change and water test
  • Filter maintenance
  • Seasonal checks for temperature swings

Next stage

From about 9 years of age your goldfish enters the senior stage.

Les tranches d'âge sont approximatives ; les différences au sein d'une espèce (comme la taille chez le chien) peuvent avancer ou retarder les transitions.

Ce contenu est fourni à titre d'information générale et ne remplace ni un examen vétérinaire ni un diagnostic. Si la santé de votre animal vous inquiète, contactez votre vétérinaire.