Abyss — Aquatic Ecosystem Simulator

What it does

Feeding

Tap anywhere in the water to drop a food pellet for 4 food from a supply that regenerates at 2.4/s up to a cap of 100. Each pellet restores 42 hunger per fish that eats it; uneaten pellets rot after 14 seconds and add pollution.

Fish stats

Every fish tracks Hunger, Health, Energy and Age. Hunger drains at 1.8/s (adult) or 3.2/s (baby) and starvation drains health fast; Energy regenerates at 4/s; fish mature from baby to adult in 26s and die of old age between 150–230s.

Water quality & pollution

A 0–100 pollution meter rises from feeding waste and rotting pellets and decays slowly on its own — Clean (0–30) lets fish regen health, Stressed (31–70) drains it, and Toxic (71–100) drains it fast and sends fish fleeing.

Fish behaviors

Hungry fish automatically chase pellets, compatible pairs mate to spawn babies and earn pearls, a starving male will prey on a nearby baby to survive, and fish flee toward cleaner water once pollution turns toxic.

Filter upgrade

Spend pearls to install a water filter, up to level 4. Each level adds 0.55/s to the base 0.7/s pollution decay rate — a maxed-out filter more than quadruples the natural cleanup rate.

Pearl economy

Pearls are earned 3 at a time for every successful birth and spent on filter upgrades (14 pearls per level) — a thriving, breeding population is the main way to afford the filters that keep pollution in check.

Survival strategy

Every decision trades off population growth against pollution load, so the game rewards pacing rather than constant feeding.

• Feed sparingly early — fewer fish means less waste
• Stop feeding once pollution enters the yellow zone and let the water recover
• Save pearls for filters — the only permanent defense against a pollution spiral
• A population boom is double-edged: more breeding earns pearls, but more mouths to feed
• Starvation can trigger predation — hungry males will eat babies to survive

Design

A single underwater tank scene with fish rendered as animated sprites carrying live stat badges, a colour-coded pollution meter (green/yellow/red) as the central risk indicator, and a pearl/food HUD overlaying the water.

Single-screen tap-to-play: tap the water to feed, tap Restock the Reef to restart after a game over. No tab navigation — population capped at 28 fish.