Fireworms vs bristols... Help a newbie please

[Tecnomantis]

Folks, I got about a million of these things.
1. Is there an invertebrate that eats them? Or fish?
2. Is it good or bad?

I am freaking out. I saw 3 when I git the rock but when the lights are out I saw like 20.

If you can tell me what the yellow think is, appreciate it!! Thanks seriously!

 

[Sk8r]

They're ordinary bristleworms, friends to your tank---especially if you're overfeeding. If you have a lot of them, it's because they have way plenty to eat, and removing them could cause an ammonia spike (from the decay of what they're eating) and kill your tank.

Slow down on the food. A fish only needs to fill its mouth once a day to survive (a few like that spread out several times during the day) and can go two weeks without eating. If there's not so much food the worms will gradually die back to a reasonable number.

Wear gloves when handling rocks where they live: it's kinder to your hands--and the worms.