WHAT EATS BRISTEL WORMS AND IS REEF SAFE?

i don't like bristle worms and i did see them catch pods too. but interesting thing that i have noticed is that fire bristle worms don't hide, like a regular bristle worms, but eat corals right in front of you. don't get an arrow crab anyway, i don't think it's a good crab. i hear they catch small fish and kill shrimps. i would rather have bristle worms.
 
Here is a pic of my one and only bristle worm. Has to be at least 8" long now. How long do these things live anyway?

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