VariableVista Interactive Science Models

Life Science · Systems Model

Virtual Fish Hatchery

Investigate how feeding, aeration, water exchange, temperature, and stocking density affect fish health and survival over time.

Grades 8–12 20–40 minutes No login required
Day 0
Fish alive 1,000
Survival 100%
Average mass 18.0 g
System health Good

Digital Hatchery

Rearing Tank

Healthy Stressed Critical
Visible fish represent groups 1 fish = 25 fish
Tank condition Stable
Dissolved oxygen 9.0 mg/L
Healthy

Low oxygen slows fish and increases mortality.

Waste level 8%
Low

Waste rises with fish biomass and excess feeding.

Stress level 7%
Low

Stress combines temperature, crowding, oxygen, food, and waste.

System Output

Population and Oxygen

Cause and Effect

What is happening?

The hatchery is stable. Feeding supports growth, aeration maintains oxygen, and water exchange keeps waste low.
Feeding
Fish growth
More biomass
More oxygen use
Extra food
Waste
Lower oxygen
Higher mortality

Latest daily report

  • Population begins at 1,000 fish.
  • Water conditions are currently favorable.
  • Press Advance One Day or allow the model to run.
Educational model limitation: This model is designed to demonstrate interacting system variables. It does not predict survival for a specific fish species or real hatchery. Actual survival depends on species, life stage, disease, genetics, water chemistry, flow, handling, and many other conditions.