Multiple bristle worms inside sea hare

[moretor1]

Came home from work today and was checking around my tank to see the worst sight I've ever seen in this hobby
Sorry for the bad pictures I was in a rush to get them out

TWO BRISTLE WORMS INSIDE MY SEA HARE

I don't care if they just wanted the poop fresh from the source one went in the back hole and came out the front hole

I will be eradicating any bristle worms that stray too far from their safe crevices... This is just too much

I threw in a nori sheet for the sea hare and caught about 5 more as they came out looking for the food

 

[moretor1]

I should clarify the sea hare is alive and unphased. Although it should feel as traumatized as I am

 

[bluemon]

Idk why people hate bristleworms so much, they are one of the best CUC.

Wait until OP sees that fish that lives INSIDE a cucumber’s anus

 

[Awesome Opossum]

I've been lurking the forum for years and joined tonight. This was the first thread after joining.

Idk why people hate bristleworms so much, they are one of the best CUC.

Wait until OP sees that fish that lives INSIDE a cucumber’s anus

https://www.australiangeographic.com.au/travel/2025/05/hinterland-oyster/
I had never heard of that and was intrigued. One had 15 living in there!

 

[vetteguy53081]

Came home from work today and was checking around my tank to see the worst sight I've ever seen in this hobby
Sorry for the bad pictures I was in a rush to get them out

TWO BRISTLE WORMS INSIDE MY SEA HARE

I don't care if they just wanted the poop fresh from the source one went in the back hole and came out the front hole

I will be eradicating any bristle worms that stray too far from their safe crevices... This is just too much

I threw in a nori sheet for the sea hare and caught about 5 more as they came out looking for the food

Good plan on removal. This is the reason I dont allow these worms into my tanks. While they eat detritus and uneaten foods, they often get into the wrong places while multiplying. A few years ago when transferring tanks, I pulled a 12 and a 14" specimen. My harlequin eats any it finds

 

[moretor1]

Ah, sadly I think the bristle worms just knew something before I did

My hair algae is mostly gone and has been for a while. I've substituted nori when I can but a bunch of stuff happened and I fell behind feeding my tanks

On top of moving the entire tank, and trying to get the it out of the moving bucket. The stress finally made it split.

I will most likely euthanize in the morning if it's not already dead

 

[bluemon]

Ah, sadly I think the bristle worms just knew something before I did

My hair algae is mostly gone and has been for a while. I've substituted nori when I can but a bunch of stuff happened and I fell behind feeding my tanks

On top of moving the entire tank, and trying to get the it out of the moving bucket. The stress finally made it split.

I will most likely euthanize in the morning if it's not already dead

Yea this is why bristleworms get a bad rap.

Pretty much when you see them “attacking” something, it’s because they were on the way out.

Sorry about the sea hare, they eat a lot so they don’t last long on just natural tank algae

 

[moretor1]

As of this morning I woke up to it in a different spot, the back is not split wide like it was last night after removing the bristle worms.

I can see the crease where it split open but the internal shell is no longer visible. I will give it time to see how it does before making a final decision. I'm hoping it may have just split from stress

I do know that splitting is not permanent if it is not actively dying, just that splitting is the most common sign of it starving to death

2-3 months ago I observed it slowly starting to split from the tail end and was able to get it to heal up by hand feeding it more.

This split happened over the course of maybe 3 hours instead of the usual days or weeks