Reef Dive: Pixel Art Aquarium & Procedural Fish Tank

Reef Dive
Life
SparseTeeming
Water & light
Keep this reef
click the water to feed  ·  click a fish to meet it

Record the reef

Keep this tab in front until it finishes — switching tabs or minimising will make it stutter.

Reef Dive

a living procedural aquarium

Every fish on screen was grown from a species genome — a body spline, parametric fin fans, a pigment program — and moves on its own boid mind. Nothing is a sprite, nothing is a loop. Corals bud while you watch, clownfish keep house in the anemones, and every so often a sea turtle or a squadron of jellyfish drifts through. Built for anyone who wants a living ocean in a browser tab.

Click the water — scatter food  ·  Poke a fish — startle it
F — feed  ·  N — new reef  ·  L — night dive
M — sound  ·  P — 4K still  ·  R — record
H — hide panel  ·  Esc — close

On a wall display or dashboard (DAKboard, a smart mirror, a spare monitor)? Add ?kiosk to the address — reef-dive.html?kiosk — and it opens full-screen with no panel, no cursor, nothing to tap. Add a shared reef link on top to pin one exact reef: ?kiosk&s=…

Record the reef as an MP4 (or WebM in Firefox, which can't make MP4) or an animated GIF — in portrait, landscape or square. GIF is a 256-colour format from 1989, so the water will band and long clips get heavy; MP4 is the better keepsake. Share copies a link that grows this exact reef again from its seed.

Foundational code from Fable Showcase by elder-plinius.

Questions

What is Reef Dive?

Reef Dive is a free, browser-based virtual aquarium and fish tank simulator. Every fish is grown from a procedural species genome — a body spline, parametric fins, and a pigment program — and swims on its own boid AI. Corals bud while you watch, kelp answers a shared current, and sea turtles and jellyfish drift through. No account, no install.

Is Reef Dive free?

Yes — completely free with no hidden limits, no account required, no watermarks, and no feature gates. It runs entirely in your browser.

How do I use Reef Dive?

Open the page and the reef grows itself. Click or tap the water to scatter food, click a fish to meet it by name, pick a dive site, and press N to grow a brand-new reef from a fresh seed. Press H to hide the panel for screensaver mode, and use the 4K button to save the view as a wallpaper. Everything runs in your browser — nothing is uploaded.

Does Reef Dive collect my data?

No. Everything runs locally in your browser using JavaScript. Nothing you do in the aquarium leaves your device — there are no servers, no uploads, and no tracking beyond basic anonymous page analytics.

Are the fish real species?

No — every species is invented on the spot. Each new reef rolls forty unique genomes that define body shape, fin geometry, swim wave, schooling behavior, and a pigment program of stripes, spots, or countershading, then gives each a plausible Latin-style name. The clownfish in the anemones is the one familiar face. For real-world varieties, try Koi Pond.

How does Reef Dive compare to SereneScreen Marine Aquarium?

SereneScreen Marine Aquarium is a classic paid screensaver with pre-modeled fish. Reef Dive is free, runs in any browser without installing anything, and generates its fish and reef procedurally — every seed is a different ecosystem. It also adds interaction: feeding, meeting fish, night dives, and 4K wallpaper export. For more generated water, see Other Oceans.

Can I use Reef Dive as a screensaver or on my phone?

Yes. Press H to hide the panel and Reef Dive becomes a full-screen ambient aquarium — ideal for a spare monitor or a calm tab. It runs on phones and tablets with touch feeding, and the 4K export makes wallpapers sized to your screen. Pair it with Tone Shelf for a full ambience mix.

How do the fish school together?

Reef Dive uses a boids flocking model: every fish steers by three local rules — separate from crowding neighbors, align with nearby schoolmates, and stay cohesive with the group — plus wander, current, food attraction, and predator fear. Schooling emerges from those rules; no path is scripted.