"night crawlers?"

[stieger]

Hi folks,
I have a 70G live rock tank with a few anemones and clownfish, and lately at night, after I turn the lights off, my son and I have noticed little "night crawlers" out and about.
They look like brine shrimp. They stay on the bottom, seem to have a bunch of legs, and don't really seem to be able to control where they walk. Once the lights go on in the morning, they seem to try and scury into the rocks as quickly as possible.
Does anybody know what these things are? I'd take a picture, but they haven't come out very clear. Again, they look like brine shrimp (a little bigger). I'm just curious if they are harmful to the fish or anemones in the tank.
Thanks all,
Stieger

 

[frozenguy]

pretty sure those are probably copepods?
if you run a media filter you can probably see them stuck in the mesh stuff when you pull it out..

 

[1fast300zx]

Sounds like copepods as stated above. They arent harmful, they come in the Live Rock.

 

[meleerock]

agreed! Totaly benifitial!

 

[m0nk]

Copepods, as the others noted. They're a sign of a healthy tank and are good to have. Some fish will eat them as a supplemental food source and they're great scavengers. Just another great form of biological "filtration" that comes as a part of having live rock.

 

[stieger]

sweet - I was worried - thinking I should skim them out of the tank, but I'll leave 'um in there! Do they multiply quickly? A month ago I only noticed about 10, now I see upwards of 30. They seem to congregate together - funny...
Thx all!
Stieger

 

[meleerock]

they mulitply quickly if nothing is eating them...lol. If there isnt a threat to them being eaten then you will notice a ton in your tank, especially at night.