Hitchhikers good and bad?

[EdsonFOWLR]

So what has everyone had come into their tanks (ie hitchhikers) that was good and what did you get that was bad?

[Scuba Diver Gal]

i get rid of everything that i didnt put into my tank.

[FishingGoalie]

oops I meant to post that but i posted it with my moms account ^^^^^

[monocus]

aptasia is always bad.sponge good

[ReEf BoSs]

In the first lr i bought i got a gray/blue pistol shrimp that i hear nightly but have only seen once in three years.

[mark]

ick - bad

[Cujo#31]

Bloody Majanos......bad
Aiptasia....... uh huh!!!!! Nasty
small clams (not tridacs) but still good, sponge, tube worms, millions of misc critters, hermits, encrusting sumthing or others........
its a crap shoot, but if it shows up and u cant identify it.....NUKE IT!!!!!!