Live rock worm

[Serafin]

Hey guys just wondering if anyone can identify the worm I have just noticed coming from under a piece of live rock. Wanted to find out if he's good or bad for my aquarium.

 

[bavass]

Hard to tell from the pic but it looks like a bristle worm they are fine and actually help keep tank clean.

 

[mr_X]

Yep. common bristle worm. Harmless scavengers.

 

[Serafin]

That's good to hear, kinda got a little worried as the thing looked a little scary looking

 

[mr_X]

They are related to the common earth worm. The spines on the sides are for defense. If you touch it, it will feel like you were playing with fiberglass.
If you see a large population of these in your tank it's because of overfeeding. Their populations grow according to how much available food there is.

 

[Serafin]

Only had the tank running a few months now and this morning was the first time I've seen any other hitch hiker other then some really really small snails. Guess the worm wanted some of them tasty new pellets I brought

 

[Texas]

Harmless for the most part but can get large enough to consume some smaller species of fish. I've actually witnessed one in my tank eating a goby. I believe the goby was dead prior to it eating it but couldn't be certain.

 

[Crystal A]

Most Lilly the goby was dead. Bristols are scavangers not killers. It was doing its job keeping the tank clean.

 

[mr_X]

Harmless for the most part but can get large enough to consume some smaller species of fish. I've actually witnessed one in my tank eating a goby. I believe the goby was dead prior to it eating it but couldn't be certain.

Yours got so large from eating plenty of delicious food. Ease up on your feedings, and you won't see them this big.