Without light guppies (and most other species of fish) can not see one another so it would be extremely difficult for them to locate one another let alone breed successfully. Therefor I would say that the effect of light would be to 'enable' reproduction of guppies.
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Dissolved gasses, light intensity, pH level, and water availibility.
Fries (the term for baby guppies), are eaten by older guppies, but guppies are eaten by fish like tuna.
Only guppies breed with guppies naturally.
What are guppies
No, guppies are fish.
Guppies do not migrate.
Guppies are surface fish and they also enjoy swimming/playing in water currents that is why they are there.
any color that is light or black with another bright florensent color.
Guppies are guppies are guppies. Tiger just describes their colouring/markings. They are the same in temperament as any other guppy.
Guppies are compatible with Bristlenose catfish, the bristlenose being one of a few catfish that can live with guppies because of the guppies' water.
The plural of guppy is guppies. The plural possessive is guppies'.