He kept the jar on a windowsill and recorded its status over weeks. The pond water inside the jar was teeming with life.

For the next part of his experiment, the camper collected the dirty pond water in a water bag and passed it through a portable filter straw. Pouring it into a cup, he was surprised to observe the ...

U nder the microscope a drop of pond scum can give hours of delightful study. What feels between the fingers like slime is, microscopically, an open lake crowded with queer vegetable and animal life.

The first is microscopic algae (commonly thought of as blue-green algae). It appears to look like a swirl of green or yellow-green oil floating on top of the pond. Microscopic algae often occur when ...