Good or Bad?

[Mr_Cool]

I have coraline algae growing on the shells of my snails and hermit crabs. Is this a problem?

It's so weird to look at the tank and see a piece of rock moving, only to look closer and see it's a snail or crab!

Do I need to do anything about this, or just let it go?

[GaryP]

Let it go! A good thing.

[JeremyGlen]

The longer the shells are in there, the more they get covered. I believe, may be wrong, they actually help spread the coralline by rubbing against the rock and spreading "spores"?

[Mr_Cool]

Great! I know it's good to have coraline growth in the tank. I just wanted to make sure it wasn't going to hurt the inverts. Thanks!

[jrnannery]

Is that how coralline spreads?

[brewercm]

That and just the spores flowing in the water column like regular algae.