Chaeto Hitchhikers

[Biggest Little Reef]

I’ve had a ball of chaeto in QT for a couple weeks now. Looking for some help identifying some of the critters I’ve observed over those few weeks. Before I start moving this chaeto over to my main tank I want to make sure they are not “pests”.

 

[Pkunk35]

Whoa the bottom one looks like some kind of medusa worm but tiny!