Why the PolyFish die
Eating in PolyFish gives you zero energy, so every creature is on a countdown clock from the moment it's born. No population caps, no spawners, just collisions and math. The population runs away and crashes on its own, every single time.
If you open PolyFish and leave it running long enough, you will eventually get a message that says the PolyFish have died. People assume I wrote that as a joke, or a sad little flourish to make you feel something. I didn’t. It’s just the true thing the math keeps doing, so I let the message say so.
Eating does not keep you alive
Here is the part that trips everyone up. In PolyFish, food gives you zero energy. None. You eat, and your life does not get one second longer.
Every creature is born with a tank of energy and that tank only ever drains. A fish starts with 60 energy points and burns them at 60 a minute, so a fish lives about a minute, give or take 30 seconds of random wobble. Dolphins and manatees get slower drain rates and live a couple minutes. That’s it. From the moment a thing is born, it’s on a countdown, and nothing it does buys it more time.
So why eat at all? Because eating is how you make babies, not how you survive. Each creature keeps a meal counter. A fish that hits 4 meals reproduces. A dolphin needs 5 fish. A manatee needs 7 grazes off the plants. Food is the price of the next generation, never a refund on your own clock.
It’s all just things bumping into things
There is no director in here telling the ecosystem what to do. The whole thing runs on collisions. Plants spit out food particles. Fish bump into food and eat it. Dolphins bump into fish and eat them. Manatees graze the plants directly. And when anything dies, it sinks to the seafloor and becomes the waste that seeds the next batch of plants. The loop closes itself.
I seed the world with 60 fish, 15 dolphins, and 10 manatees, and then I get out of the way. There are no spawners topping the numbers back up. No hard cap saying “okay, that’s enough fish now.” Everything alive in there, after the first few seconds, got there because two creatures ate enough to breed. Every fish you see earned its spot.
The crash is the honest answer
Take the caps off and feed nobody any extra life, and you get exactly what you’d expect, just faster. The fish breed, the food’s everywhere, the population blows right past the numbers I started with. Then there are too many mouths, the food can’t keep up, the drain clock never stops, and the whole thing falls over.
I watched it crash over and over while I was building it, and my first instinct was to “fix” it with a population ceiling. I’m glad I didn’t. An invisible wall would’ve been the fake version. This way the rise and the fall both come from real pressure, and when the tank finally hits zero on the last one, the screen tells you the plain truth.
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