moss balls?

If you roll it in a big enough ball you might could use it to wash your car with ;)
 
it photosynthesizes to get energy to grow. aside from what it literally does, it is an aquarium decoration. if simply being a decoration means it has "no actual point", then yes. it has no actual point. it won't start spawning fish. it won't cure ich. it won't kill snails. it won't really feed your fish. it won't wash your car.

Was meant as a joke from your reply above
 
Um, from what I remember, Marimo balls are moss, not algae, usually like java, that originated in Japanese ponds, moving slowly back and forth to form oval or ball forms in different sizes. Therefore, you could conceivably make your own, which alot of people do now and charge as much as for the real deal.
 
No you've got MY attention. What is the formal name?
They're called Marimo Moss Balls or Japanese Moss Balls or some combination of those words (japanese marimo moss balls even)
But the name of the algae itself is a cladophora algae. the full name i can't remember off the top of my head but you should be able to find info on cladophora.
 
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