Parent and child's hands together, gently lowering a bag of fish into a warmly lit planted aquarium glowing emerald and amber

Koi Aquarium School

Learn to keep
the wonder alive.

Hands-on classes for families, homeschoolers, and anyone who's ever watched a fish and felt the urge to understand it.

Every class is a world
waiting to be entered.

From your first tank to breeding rare shrimp — the grid below tells the story of a family growing in skill together. Browse beginner to advanced, left to right, top to bottom.

Close-up of colorful aquarium water test tubes being held up to light showing ammonia and nitrite readings
BeginnerAges 10+ and adults

The Nitrogen Cycle

Why your fish keep dying — and how to stop it.

A parent holds a test tube up to the light, reading ammonia levels for the first time, eyes wide.

Take home: A water testing kit and the confidence to read what your tank is telling you.

1.5 hours
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Lush planted aquarium aquascape mid-trim with dense green carpet plants and driftwood creating a miniature forest
IntermediateAges 12+ and adults

Aquascape Fundamentals

A garden that breathes underwater.

A teenager trims a lush carpet of dwarf baby tears, scissors in hand, the tank a perfect emerald rectangle.

Take home: A planted aquascape layout using the golden ratio — yours to take home.

3 hours
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Vibrant blue and red betta fish with flowing fins against a softly lit planted aquarium background
BeginnerAll ages

Betta Biology & Care

One fish. A whole world.

A family crouched around a single betta bowl, watching the fish flare its fins, everyone leaning in.

Take home: The actual reason bettas die in bowls — and a proper setup plan.

1.5 hours
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Child using a small fine mesh net to catch tiny live daphnia water fleas in a clear water container
IntermediateAges 8+ with adult

Live Food: Daphnia Culture

Grow your own fish food from scratch.

Tiny hands hold a fine mesh net over a bucket, catching clouds of daphnia, delighted and slightly grossed out.

Take home: A starter daphnia culture in a 1-gallon container, ready to feed your fish.

2 hours
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Stunning crystal red shrimp with white and red banding crawling on green aquatic moss in a nano shrimp tank
AdvancedAges 14+ and adults

Breeding Crystal Shrimp

The most beautiful 2 cm animal you'll ever keep.

A parent and child peer through a magnifying glass at a berried female crystal red shrimp, whispering.

Take home: A breeding colony starter kit and water parameter cheat sheet.

4 hours
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Family huddled around a microscope examining a glass slide with aquarium water, looking at microorganisms
IntermediateAges 8+ with adult

What Lives in Your Water

The invisible ecosystem you're already managing.

A family of four huddles around a compound microscope, watching paramecia spiral through a drop of tank water.

Take home: A slide preparation kit and field guide to freshwater microorganisms.

2 hours
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Child kneeling at the edge of a backyard koi pond with orange koi visible beneath lily pads in clear water
IntermediateAll ages with adult

Backyard Pond Ecology

From a half-barrel to a living koi pond.

A child kneels at the edge of an outdoor pond, watching a flash of orange turn slowly beneath lily pads.

Take home: A pond plant selection guide and seasonal maintenance calendar.

3 hours
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Parent and child both leaning over a planted aquarium together, the child pointing at something moving in the water, faces soft and curious

We built Koi because fish
deserve better teachers.

Most aquarium advice comes from pet store employees incentivized to sell you things. We're instructors first. We'd rather send you home with a working tank than a full shopping cart.

The moment a child understands why their fish needs a cycled tank — not just "clean water," but the actual chemistry of ammonia and beneficial bacteria — something shifts. They stop seeing a pet and start seeing an ecosystem. That's what we're after.

Hands on every surface

No PowerPoints. Every concept is demonstrated in a working tank. You leave with substrate under your fingernails and a tank that proves you understand it.

Built for families, not just hobbyists

Classes are designed so a six-year-old and their parent can both be the expert by the end. Biology, chemistry, and wonder — together.

Curriculum your homeschool can use

Each class maps to life science standards and comes with a take-home guide. Aquariums make abstract biology tangible and alive.

1,200+

Families taught since 2019

94%

Of students keep their fish alive after 6 months

38

Different species covered across all classes

4.9

Average class rating out of 5

What families take home

"My nine-year-old now explains the nitrogen cycle to her grandparents. At dinner. Unprompted. Koi gave her a language for something she already loved."
Mara Thibodeau, smiling woman with warm brown hair, homeschool mom

Mara Thibodeau

Homeschool mom of three · Portland, OR

01 / 04

You're not just keeping fish.
You're keeping wonder.

Every class at Koi ends with a living system in your hands. Something you built, something that breathes, something that will outlast the weekend. Come see what we mean.

No experience neededAll materials includedSmall class sizes (max 8)Weekends & weekday mornings
Browse All Classes