Critters, Detritivores, Biodiversity: Helpful?

[LadyTang2]

Small creatures that come with live sand or rock like small worms, stars, tiny snails, other detritivores. People say they are great to have but...

How specifically do they benefit the tank? I understand they can consume detrititus, but they poop too, so I dont see the net decrease in crap. Help me understand! I'm looking forward to some clear and understandable benefits but expecting vague anecdotes

 

[Tahoe61]

An example might be Stomatella, they eat a lot of film algae, so good.
Bristle worms eat left over foods that migrate to areas not easily accessed by fish or other inverts, a good thing.

So many of these critters consume organics, than produce organics more easily removed from a tank.

I only used two examples, there are many.

 

[NashobaTek]

If you follow the cycle all the way down to the smallest pod, you eventually have easier removal of crap.