Breed Goldfish

Goldfish Breeding Simulator: Practice Your First Spawn

Your goldfish just spawned, and the adults are still swimming right next to the eggs. Can you get this clutch all the way to growing fry? Pick one of three scenarios, make six care choices, and fix any mistake before you move on.

The nurseryReady when you are
  1. 1Protect the eggs
  2. 2Set the flow
  3. 3Watch the hatch
  4. 4Offer first food
  5. 5Manage leftovers
  6. 6Plan the next stage
Spawning complete
Illustrated tank with adult goldfish beside green strands covered in eggs
Current focusProtect the eggs

The tank is a simple drawing. It can’t predict hatch dates, survival, or how many fish a tank can hold.

Scenario 01 · About 5 minutes

Your first clutch has arrived.

A nursery tank and fry food are ready. Read what you see in the tank, then pick your next move.

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The decisions you will practice

Three scenarios, from first eggs to sick fry

01

Your first clutch

Move a fresh spawn, watch it hatch, and plan for the growing fry.

  1. Where should the eggs go?
  2. How will you set the air supply?
  3. What tells you it’s time to start feeding?
  4. Which feeding plan will you try?
  5. What do you do next?
  6. What should happen before you breed them again?
02

Surprise spawn

Handle an unplanned spawn in a tank full of other fish.

  1. What do you decide first?
  2. How do you save some?
  3. How do you set it up?
  4. What do you do with them?
  5. What’s your plan as they grow?
  6. What do you do with the extras?
03

Sick fry

Find and fix the problem when young fish start gulping at the surface.

  1. What do you check first?
  2. What do you do now?
  3. What changes?
  4. How do you clean it?
  5. What’s your next step?
  6. What becomes part of your routine?

Take the next step with your own tank

Read about goldfish tank mates that live well together before you add to an adult group, and pick the best substrate for goldfish before you change a setup.

For a planned spawn, learn how to make a spawning mop. If you have already found eggs, follow what to do when goldfish lay eggs for the nursery and first feeding.

To grow algae that feeds tiny live foods, learn how to make a green water culture. Start it early, since a new culture takes time to grow.

When a real spawn happens, the goldfish fry growth chart tracks your batch from hatch day on, with a daily care checklist.

Care sources

Every choice in the game is based on these guides.