How did I get bristle worms?!? Are there more?

mizimmer90 · Dec 6, 2022

Just happened to walk past my tank with the lights off and noticed something lurking around... upon closer inspection I saw it was a fairly long bristle worm!!! Eeeek!!

I panicked, grabbed my tweezers and fished him right out! Flushed him.. Poor little guy didn't even put up a fight and I actually feel really bad for it... pic below is after I poured some freshwater on it (curled up instantly)

My big question is: how the hell did I get it? My tank has had corals in it for about a month (all small frags). I started the tank with dry rock and sand and dipped everything before going in. Did something come in a frag as a microscopic baby and grow this massive in a month??? Are there more lurking (I assume yes)?

And don't reply telling me they're beneficial lol. Granted, I had way more empathy for it than I was expecting, but I'm not about having a tank full of things that make me scared to put a bare hand in!

Ben.QLD2 · Dec 6, 2022

You will have way more than you can see. Like most marine organisms, bristleworms have a planktonic stage. Very easy to incidenctally acquire, very difficult to eradicate. Control numbers by trapping if need be but just learn to live with them.

Jekyl · Dec 6, 2022

Free CuC

EeyoreIsMySpiritAnimal · Dec 6, 2022

They are pretty much unavoidable, you definitely have more, and they are awesome for your tank!

Idech · Dec 6, 2022

I hate them but they seem unavoidable, even if you dip.

mdb_talon · Dec 6, 2022

mizimmer90 said:
And don't reply telling me they're beneficial lol.

Well all I have to say is...they are beneficial

mizimmer90 · Dec 6, 2022

Ben.QLD2 said:
You will have way more than you can see. Like most marine organisms, bristleworms have a planktonic stage. Very easy to incidenctally acquire, very difficult to eradicate. Control numbers by trapping if need be but just learn to live with them.

How fast can they grow? I'm mostly amazed that it grew this big (from potentially a plankton phase) in a month! Is it just microscopic on some coral?

EeyoreIsMySpiritAnimal · Dec 6, 2022

mizimmer90 said:
How fast can they grow? I'm mostly amazed that it grew this big (from potentially a plankton phase) in a month! Is it just microscopic on some coral?

Yours doesn't look that big in the photo... How long was it?

mizimmer90 · Dec 6, 2022

Erin1971Texas said:
Yours doesn't look that big in the photo... How long was it?

The photo is after it curled up from plunging in freshwater (definitely shrunk up). Stretched out, it was easily 7-8 inches. How big can they get?

areefer01 · Dec 6, 2022

mizimmer90 said:
Just happened to walk past my tank with the lights off and noticed something lurking around... upon closer inspection I saw it was a fairly long bristle worm!!! Eeeek!!

I panicked, grabbed my tweezers and fished him right out! Flushed him.. Poor little guy didn't even put up a fight and I actually feel really bad for it... pic below is after I poured some freshwater on it (curled up instantly)

My big question is: how the hell did I get it? My tank has had corals in it for about a month (all small frags). I started the tank with dry rock and sand and dipped everything before going in. Did something come in a frag as a microscopic baby and grow this massive in a month??? Are there more lurking (I assume yes)?

And don't reply telling me they're beneficial lol. Granted, I had way more empathy for it than I was expecting, but I'm not about having a tank full of things that make me scared to put a bare hand in!

You are asking the wrong question. The question you should be asking is why do you care.

As an aside - glove up when putting hand in the tank. Doesn't hurt going bare but save that for other activities.

mizimmer90 · Dec 6, 2022

Jekyl said:
Free CuC

Erin1971Texas said:
They are pretty much unavoidable, you definitely have more, and they are awesome for your tank!

mdb_talon said:
Well all I have to say is...they are beneficial

Okay, for those of you saying they're beneficial, are you not worried about getting stung by them? My biggest fear is putting my bare hand into the tank and grabbing a big Ole worm

bakbay · Dec 6, 2022

Indeed -- I went through several stages of this. At one time, there was an over population of them (possibly thousands) in my tank. Now I'm only seeing 5-10 when lights go out. I suspect they've been eradicated due to starvation since there are no known predators in my tank.

bakbay · Dec 6, 2022

mizimmer90 said:
Okay, for those of you saying they're beneficial, are you not worried about getting stung by them? My biggest fear is putting my bare hand into the tank and grabbing a big Ole worm

Yes, that can be very painful! I never put my bare hand in the tank -- either wear gloves (extra long gloves are awesome) or use tongs.

mdb_talon · Dec 6, 2022

mizimmer90 said:
Okay, for those of you saying they're beneficial, are you not worried about getting stung by them? My biggest fear is putting my bare hand into the tank and grabbing a big Ole worm

I have several hundred gallons of frag tanks I am constantly putting hands in and out and probably get bristles once every couple weeks. Hurts a very little bit initially. After that just very minor discomfort until a few days later it usually gets really itchy for me for a day or two and some skin may peel off. Really that sounds a lot worse than it is lol, but really it not so bad.

Scorpius · Dec 6, 2022

Good clean up crew member. Ocean creatures are amazing and bizarre. Welcome to the hobby. Find something else to worry about, like how to implement parameter stability in your reef tank.

ReefGuard Systems · Dec 6, 2022

They gross me out... but they are good for your tank

If there is 1 there is more...

EeyoreIsMySpiritAnimal · Dec 6, 2022

mizimmer90 said:
Okay, for those of you saying they're beneficial, are you not worried about getting stung by them? My biggest fear is putting my bare hand into the tank and grabbing a big Ole worm

In my 7 years of reefing, I have handled countless pieces of rock (even ones I knew had bristleworms hiding in them), sifted through the sand, and fragged a bunch of coral that was on rocks, all bare handed, and have never been stung. Or, if I was, the result was just a mild irritation.
The worms are going to avoid being out in the open, especially when the lights are on, so the chances of you randomly accidentally "grabbing" one are very slim.

mizimmer90 · Dec 6, 2022

mdb_talon said:
I have several hundred gallons of frag tanks I am constantly putting hands in and out and probably get bristles once every couple weeks. Hurts a very little bit initially. After that just very minor discomfort until a few days later it usually gets really itchy for me for a day or two and some skin may peel off. Really that sounds a lot worse than it is lol, but really it not so bad.

Not gonna lie, that sounds terrible lol. A few days of discomfort every 2 weeks is ~1/5th of your life dealing with bristle worm stings!

Deff hoping to avoid that.

areefer01 said:
You are asking the wrong question. The question you should be asking is why do you care.

As an aside - glove up when putting hand in the tank. Doesn't hurt going bare but save that for other activities.

Aside from the fear of stings, I also want to enjoy the tanks beauty! Not to be prejudiced but I have a hard time doing that knowing they're lurking under the rocks lol

EeyoreIsMySpiritAnimal · Dec 6, 2022

Like other random cuc critters (the ones you didn't knowingly put in your tank), populations will respond to the level of extra food in the tank. If you start to see "too many" of any critters, reduce your feeding. (I used quotation marks because too many is subjective.)

Jekyl · Dec 6, 2022

mizimmer90 said:
Okay, for those of you saying they're beneficial, are you not worried about getting stung by them? My biggest fear is putting my bare hand into the tank and grabbing a big Ole worm

You shouldn't be rooting around in the tank that often.