Some scientists do regard coral reefs as living organisms because they are colonies of tiny, living organisms.
tiny food. Cabage or flakes
Someone who wanted to examine tiny organisms would have to use a microscope.
Almost certainly some other planets have tiny one-celled organisms, at least.
Matter.
mitochondria
microorganisms
tiny seaweeds...
Microorganisms, such as bacteria, viruses, and some types of fungi and protists, are tiny organisms that are typically invisible to the naked eye and require a microscope for viewing. These organisms play crucial roles in various ecosystems and can have both positive and negative effects on human health.
Simple answer is tiny organism's. but to get in detail it was tiny bugs and organisms in a pond.
Plankton?
because they are very tiny organisms only seen by a microscope.