Peg, I wasn't joking.
As Alan ( the other one) says, use acrylic, and use the fluffier one,
Use differnt colors for color coding, either for species or dates.
Before reusing the mop from one species to another, boil the mop, or use real hot water, to kill any surviving eggs from previuos attempts at breeding.
Eggs can survive for weeks, sometimes months, in a damp situation.
Alan