Design your dream fish tank. Add fish, plants, and decorations — then watch it come alive.
Show off your fish tank!
Aquarium Builder is a free, relaxing browser game where you design and populate your own virtual fish tank. Choose from 20 fish species, 10 plant types, 15 decorations, and 6 background themes. Watch your fish swim with species-appropriate behavior — tetras school together, bettas patrol their territory, catfish cruise the sandy bottom. The simulation runs entirely in your browser with no downloads required.
The best fish for beginners are hardy, peaceful species. Top choices include Betta fish (one per tank), Goldfish, Zebra Danios, Guppies, Platies, and Corydoras catfish. These species tolerate a range of water conditions and are widely available.
Choose a tank size, rinse gravel and decorations, install a filter and heater, fill with dechlorinated water, and let the tank cycle for 4–6 weeks before adding fish. This nitrogen cycle establishes beneficial bacteria that convert toxic ammonia into less harmful nitrates.
Compatible fish share similar water temperature, pH, and temperament. Good community fish include tetras, danios, rasboras, corydoras, and most livebearers. Avoid mixing cichlids with peaceful community fish, and never keep two male Bettas together.
Terrarium Builder · Ecosystem Builder · Coloring Book
Last Updated: March 2026
Build a beautiful aquarium with 20 fish species, plants, and decorations. Watch them swim in your custom tank. Free and relaxing. Over 12 million US households have a home aquarium, making fishkeeping one of the most popular hobbies in America.
Aquarium Builder is a free, relaxing browser game where you design and populate your own virtual fish tank. Choose from 20 fish species, 10 plant types, 15 decorations, and 6 background themes. Watch your fish swim with species-appropriate behavior.
The best fish for beginners are hardy, peaceful species that tolerate a range of water conditions. Top choices include Betta fish (one per tank), Goldfish, Zebra Danios, Guppies, Platies, and Corydoras catfish.
Setting up an aquarium involves several steps: choose a tank size, rinse gravel and decorations, install a filter and heater, fill with dechlorinated water, and let the tank cycle for 4–6 weeks before adding fish.
Compatible fish share similar water temperature, pH, and temperament. Good community fish include tetras, danios, rasboras, corydoras catfish, and most livebearers like guppies and mollies.
Last Updated: March 2026