Moving small feather dusters

[PFisher]

What is the best way to move the small feather dusters that come in on live rock. I want to move some from a refugium to the main tank.

Second question: Would the reason that I don't have many in the main tank be due to one of the following being a natural predator?

Six-line Wrasse
Sailfin Blennie
Osc. Clown
Blue leg hermit
Scarlet hermit
Turbo snail
Turban snail