what the heck are these???

[makoJ]

ok last night happen to shine a light in the tank and hundreds of these red/pink and blue worm things are swimming around.

The snail in some of the pictures is almost 3 inches long to give some perspective. They weren't attacking the snail but resting from the flow I didn't see them do anything but swim around
Both the red and blue worms swam the same kind of looked like a centipede

 

[makoJ]

 

[LeslieH]

You just had a spawning event in the tank. these are epitokes of polychaetes worms in the family Syllidae. The worms are quite small and a big healthy tank could have thousands of them living in sponges, rock crevices, among epifauna, etc. Harmless. Each worm produces eggs or sperm which is moved down to the posterior part of the body. The posterior part becomes modified with special bristles for swimming and develops eggs (the little red dots). this portion is called the epitoke. Simultaneously all the epitokes wil break off & swim into the water, then the skin breaks open & the eggs & sperm mix for external fertilization.

 

[makoJ]

wow thanks for the info!

 

[LeslieH]

You might have some recruitment but the majority of the gametes will be skimmed or eaten. Inverts like cavier just as much as people do!

 

[colotl]

I was shinning a flashlight last night and whereever I moved these same creatures followed it. Glad to here that they are harmless. There's lots of them in my system

 

[Elysia]

Each worm produces eggs or sperm which is moved down to the posterior part of the body. The posterior part becomes modified with special bristles for swimming and develops eggs (the little red dots). this portion is called the epitoke. Simultaneously all the epitokes wil break off & swim into the water, then the skin breaks open & the eggs & sperm mix for external fertilization.

Leslie, do you know of any other animals that reproduce like this? It is both and creepy at the same time -- I mean, can you imagine brainless bodies that exist only to have sex (well, besides some humans!) roaming the earth.... but at the same time, what an extraordinary way to deal with the predation that occurs in the ocean when animals attempt to get close enough to one another to reproduce. Almost like a lizard dropping its tail (if that tail could also get up and carry sperm to some other lizard tail with sperm in it!) Its just trippy. Truth is stranger than fiction, sometimes.

 

[EaZy DuZ iT]

I wish i had those little guys!

 

[fiddly_foo]

lol i've been wondering what those are in my tank at night that follow my flashlight been asking so many people thats cool to know like evry month or so I get them wonder if my coral eats them when they swim into there polyps..?