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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The key is maintaining a healthy population 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 meters: O₂ (oxygen limits total population), nutrients (feeds algae), pollution (from rotting food/dead bodies), and CO₂ (byproduct). If pollution gets high, stop feeding and let nature clean up.
Fish die when their energy reaches zero. This happens if: (1) They cannot find enough food (daphnia/zooplankton), (2) Oxygen levels are too low (O₂ < 20 causes rapid energy loss), (3) Pollution is too high (>50 hurts fish especially), or (4) You added too many predators. Try feeding them manually by dropping food, but do not overfeed!
During daytime, algae perform photosynthesis — they consume CO₂ and produce O₂. At night, photosynthesis stops, so O₂ slowly decreases while all creatures continue consuming it. Daphnia also become more active and swim upward at night. Plants also produce extra O₂ only during daytime.
When creatures die or food rots (after 400 ticks uneaten), they become brown waste particles that slowly sink. Over time, these waste particles decompose into nutrients (shown in the green Leaf meter). Nutrients then boost algae growth rate — creating a full circle: death feeds new life! This mimics real-world nitrogen cycling.
Yes! Each terrain type has a real effect: Sand boosts algae growth within 60px radius (simulating bacteria). Plant tiles produce extra O₂ during daytime (+0.015 per plant). Rock tiles push away any creature that comes 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 rots and increases pollution, which hurts all living things. Tips for a Healthy Tank: 1. Start with plenty of algae and some sand (they are the foundation of the food chain) 2. Add plants for extra oxygen production 3. Do not add too many predators too quickly — population is limited by O₂ levels! 4. Do not overfeed! Rotting food creates pollution that harms all creatures 5. Use rocks strategically to guide creature movement 6. Watch the nutrient meter — it rises from decomposition and helps algae grow
Benefits: - Learn about ecological relationships, food chains, and nutrient cycling - Develop systems thinking and resource management skills - Experience calming, meditative gameplay with meaningful choices - Understand basic concepts of photosynthesis, gas exchange, and decomposition - Enjoy satisfying simulation gameplay where every action has consequences