Ecosystem Tank — Aquarium Simulator
Build and manage your own underwater ecosystem! Watch the food chain in action: Algae → Zooplankton → Daphnia → Fish. Balance O₂ and CO₂, experience day-night cycles, and enjoy this calming ecosystem simulator. Perfect for stress relief and learning about ecology.
Frequently Asked Questions
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How do I keep my ecosystem balanced?
The key is maintaining healthy populations at each level of the food chain. Start with lots of algae and some sand, then gradually add zooplankton, daphnia, and finally fish. Monitor all four indicators: O₂ (limits total population), nutrients (feeds algae), pollution (from uneaten food/corpses), and CO₂ (byproduct). If pollution gets too high, stop feeding and let nature clean itself.
Why do my fish keep dying?
Fish die when their energy reaches zero. Common causes: (1) Not enough food (daphnia/zooplankton), (2) Oxygen too low (O₂ < 20 causes rapid energy drain), (3) Pollution too high (>50 especially hurts fish), (4) Too many predators. Try manually dropping food to feed them, but don't overdo it!
What does the day/night cycle do?
During the day, algae perform photosynthesis — consuming CO₂ and producing O₂. At night, photosynthesis stops, O₂ slowly drops while all creatures continue consuming it. Daphnia also become more active at night and swim upward. Plants also only produce extra O₂ during daytime.
How does the nutrient cycle work?
When a creature dies or food sits uneaten for 400+ ticks, it becomes a brown waste particle that slowly sinks. Over time, these waste particles decompose into nutrients (shown in the green leaf meter). Nutrients then boost algae growth rate — completing the circle: death nourishes new life! This mimics the real-world nitrogen cycle.
Do terrain decorations actually do anything?
Yes! Each terrain type has a real effect: Sand boosts algae growth within 60px radius (simulating bacteria). Plants produce extra O₂ during daytime (+0.015 per plant). Rocks repel any creature entering within 12px, acting as barriers. Place them strategically to shape your ecosystem!
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About Ecosystem Tank
How to Play: - Feed your fish by clicking on empty water spaces (food decays into waste over time!) - Add creatures using the +Fish button or draw algae with the brush tool - Decorate your tank with sand, rocks, and plants using the drawing tools — each affects the ecosystem differently! - Monitor the O₂, CO₂, nutrients, and pollution levels — balance is key to a healthy ecosystem! - Watch as algae produce oxygen during daytime through photosynthesis (faster near sand!) - Observe the food chain: Algae → Zooplankton → Daphnia → Fish - See dead bodies decompose: waste particles sink, then break down into nutrients that feed algae growth - Rocks push creatures away; plants add extra oxygen during daytime Ecosystem Mechanics: Every creature has energy that depletes over time. They must eat to survive. When a creature dies, it becomes waste that pollutes the water. Over time, waste decomposes into nutrients that help algae grow. Algae need sunlight, CO₂, and nutrients to thrive and produce oxygen. At night, photosynthesis stops and the ecosystem relies on stored oxygen. Terrain Effects: Sand tiles boost nearby algae growth (bacteria provide nutrients). Plant tiles produce extra O₂ during daytime. Rock tiles repel creatures, creating natural barriers. Too much uneaten food or dead creatures pollutes the water, hurting all life. Tips for a Healthy Tank: 1. Start with lots of algae and some sand (they're the foundation of the food chain) 2. Add plants for extra oxygen production 3. Don't add too many predators at once — population is limited by O₂! 4. Don't overfeed! Rotting food creates pollution that hurts everyone 5. Place rocks strategically to guide creature movement 6. Watch the nutrient bar — it rises from decomposition and helps algae grow
Benefits: - Learn about ecological relationships, food chains, and nutrient cycles - Develop systems thinking and resource management skills - Enjoy a calm, meditative gameplay where every choice matters - Understand basics of photosynthesis, gas exchange, and decomposition - Experience meaningful strategic simulation gameplay
