Water Kiwoogi

We don’t keep fish, we keep water

Water Kiwoogi is an aquarium simulator that calculates how the water in a tank changes day by day. Choose the tank size, substrate, filter, light, CO₂, heater, plants, fish, and your feeding and water change habits, and it calculates that tank’s water hour by hour for 30 to 180 days.

What it calculates

• Cycling — how long until filter bacteria can handle ammonia and nitrite
• Ammonia · nitrite · nitrate — how waste from food and livestock builds up and gets removed
• Dissolved oxygen — temperature, surface agitation, and the oxygen plants and bacteria use when the lights go off
• pH and KH — how CO₂ injection, substrate, stone and driftwood raise or wear down buffering
• Algae and plants — whatever light and nutrients the plants can’t use, algae take
• 80 fish and invertebrates, 51 plants, 16 tanks, 62 pieces of equipment, chemicals, substrates, stones and driftwood

Two modes

• Game — design a tank, run it, and get a score and an ending. Even failures come with a cause and a fix.
• Tool — enter readings from your real tank to forecast its water and see what to change. With two readings, it back-calculates your tank’s bacteria so the forecast gets more accurate.

Principles

• No luck. The same design always gives the same result, so you can tell a better design from a lucky run.
• No hidden numbers. Every value the calculation uses is published in the catalog.
• One engine for both. What you learn in the game carries straight over to forecasting a real tank.

Please note

Water Kiwoogi is a model built on published fishkeeping knowledge and research; real tanks behave in far more varied ways. Use the results as a guide for your own judgment. If you’re worried about your livestock’s health, please ask a local aquarium store or an expert.

Who made it

Built and run by an individual developer in Korea. Free to use, with no sign-up and no payment. Leave reviews, odd results or wishes in the Feedback tab on the site — every one gets read.

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