[Michael]

Just witnessed something I havent seen before in my tank. Have a fairly healthy population of Bristleworm in the tank. Most are fairly small apr 1 to 1.5 inches long. There is one huge specimen though which I occaisionally see. It is atleast 6 inches long.

Today while I was observing the tank, tank lights were on in the early afternoon, the large bristleworm stuck one end out of the rockand excreted a long stream of white fluid. Dont have to tell you what it looked like. The entire tank went cloudy white. Immediately thereafter all the other bristleworms in the tank started coming out of hiding, climbed up too a higher point, and began excreting a stream of what looked like pink fluid. Once done, they went back into hiding. It appears to me I witnessed the breeding process bristleworm style.

Interesting to watch but I think its time I trapped the larger out of the tank. Protein skimmer is working overtime to clear the tank.

Anyone evr seen this before and any thoughts on whether these very large bristleworms are a benefit or detriment to the tank

[wozza]

haha wow thats messed up!

[sihaya]

Sounds like spawning maybe?

[charlie]

Originally Posted by sihaya

Sounds like spawning maybe?

That would be a pretty good guess I think.

[Ninong]

Originally Posted by Michael

Just witnessed something I havent seen before in my tank. Have a fairly healthy population of Bristleworm in the tank. Most are fairly small apr 1 to 1.5 inches long. There is one huge specimen though which I occaisionally see. It is atleast 6 inches long.

I purchased a dozen baby bristleworms (Eurythoe complanata) from www.inlandaquatics.com a few weeks after starting up my 120-gal tank. They were all about 1" long when I got them and within two to three months I had lots of them in the 4"-7" long size. They can grow very fast under the right conditions.

Today while I was observing the tank, tank lights were on in the early afternoon, the large bristleworm stuck one end out of the rockand excreted a long stream of white fluid. Dont have to tell you what it looked like. The entire tank went cloudy white. Immediately thereafter all the other bristleworms in the tank started coming out of hiding, climbed up too a higher point, and began excreting a stream of what looked like pink fluid. Once done, they went back into hiding. It appears to me I witnessed the breeding process bristleworm style.

What you witnessed was a mass spawning. Polychaetes spawn en masse on the GBR and this has been filmed. I have it in one of my tapes but I can't find it right now to give you the correct title. In our tanks, actual reproduction is asexual but that doesn't stop them from spawning anyway.

Interesting to watch but I think its time I trapped the larger out of the tank.

I wouldn't remove it. It's a beneficial scavenger.

Anyone evr seen this before and any thoughts on whether these very large bristleworms are a benefit or detriment to the tank

It's a benefit until and unless proven otherwise. Almost all "bristleworms" are beneficial. There are exceptions but the great majority are good guys.

[Michael]

Thanks guys. I thought right away it was a spawn. Interesting to watch how they all came out to play. Tank is still a bit cloudy but is clearing.

I knew bristleworms are a beneficial scavenger but thought I had read somewhere that the very large ones should be removed. So far I havent witnessed him doing any harm other than freaking out the fish today by clouding the tank. Guess Ill just leave him be.