How fish can be present in 4th floor without adding by somebody

[Aniket]

I went to my friends shop. Upper floors are under construction from 2 years. I just went on 4th floor so i found guppies in stagnant water. And lots of algae in it. I asked my friend who put guppies in it but he said no one come here. So i was wondered. Is it possible to generate fishes like that?

 

[Colin_T]

Somebody put them in there, or they got picked up from a lake or pond by a cyclone/ typhoon and dropped there.

It happens sometimes in Australia and other countries that have cyclones. The storm picks up pools of water from the ground and drops it somewhere else. Sometimes fish are in the pools and get moved. Other times the fish get thrown out of the cyclone and you get fish dropping from the sky.

 

[NickAu]

Maybe they were being chased by fishermen and Capt Kirk beamed them up?

 

[Jeremy180]

Have heard of water birds (and Presumably others, like Jays, crows, etc.) carrying fish to other bodies of water before attempting to eat them, then accidentally dropping the still living fish as one method of wild fish moving between bodies of water.

In the case of guppies, it only takes a single pregnant female.

Also heard of Fish sometimes spreading via eggs stuck to the feet of water birds, but this would not be the case with guppies, obviously