You can not see through Guppies. You may well be able to see into some of them and see some of their internal organs. The reason for this is the lack of reflective material in some of their scales which allows some light to penetrate thus allowing some vision.
Yes, they can see people.
Guppies are livebearers. So they don't lay eggs. Male guppies WILL eat their own baby guppies. They will eat any baby guppy they see. It doesn't matter if it's their own or some other guppies'. Male and female guppies eat baby guppies.
Some of them will get eaten, but what you can do to help is to have a plant that is small enough for the baby guppies to swim through. It will protect them when they are that young.
yes,guppy breath through their gills because it is a fish
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Being fish, guppies do not have lungs. They breathe through gills.
Fries (the term for baby guppies), are eaten by older guppies, but guppies are eaten by fish like tuna.
What are guppies
Only guppies breed with guppies naturally.
No, guppies are fish.
Guppies do not migrate.
Guppies are compatible with Bristlenose catfish, the bristlenose being one of a few catfish that can live with guppies because of the guppies' water.