ID these cotton like balls??

[nvatlantis]

Can anyone tell me what they are and if they are bad?

 

[Highgrade]

Pineapple sponge most likely

 

[nvatlantis]

Pineapple sponge most likely

there are quite a few is this common?

 

[Auquanut]

there are quite a few is this common?

Yes. Very common. They are good filter feeders and a sign that the tank is stabilizing. I've noticed that as my tank matures, I see less and less of them.