..what do you think this is? Parasite? Critter?

[Zaffy]

They're obviously http://en.wikipedia.org/wiki/Rod_(cryptozoology)

 

[Reframer]

Just stop looking at your water that closely, you'll start seeing a lot of freaky things. You know, there are many kinds of microorganisms in there, whether we can see them or not.

 

[CEEEYE]

I agree ,but if it bugs you out get a cheap air powered corner filter to over filter and crank it up plus water changes.Take a couple of samples and add bleach and some other poisons ,if it is biological it will stop moving

 

[vampie]

It wouldn't be so much a problem if there weren't so much that it has become a huge eyesore even from across the room, not to mention this could be what has caused DOAs in a recent shipment.

..I think this may be as frustrated as I've ever been as an aquarist.

 

[ibr3ak]

Planaria?

 

[CEEEYE]

planeria looks like worms that wiggle

 

[Reframer]

Oh, I see. One time I made a water change in to a clear bucket and when I saw the water looked cloudy I notice hundreds of nematodes. I didn't know what they were at first and freaked out. I just stopped looking at the water change bucket after that experience. I also notice things in my gravel from time to time and just vac them out and look away.
http://www.planetinverts.com/what_is_that_bug_in_my_aquarium.html

 

[vampie]

Well, it's definitely not planaria or nematodes. I can tell those from a mile away. Not literally of course.

Whatever they are, it looks like they have no trouble getting past the prefilter, as a water sample from inside the filter shows.. doubt the floss is helping much either. Then again, Aquaclears were never good for fine mechanical filtration, given all the bypass it allows.

Guess I'll fast the tank and up the water changes and see if it'll make a difference.

 

[jlink17]

Keep us updated. I am intersted in what you find out it is.

 

[dundadundun]

Take a couple of samples and add bleach, if it is biological it will stop moving

that's a good point... worth a check in a glass if it bothers you. can't see using micron pads on an aqua clear. a small uv sterilizer should do the trick though. or switch to a canister and add micron media. neither of those options are too happy on the pocket though.

have you seen all of these? http://forum.punkyfish.nl/board/www/forum.php/list_messages/54020
or this might help for id also: http://www.plantedtank.net/forums/shrimp-other-invertebrates/40061-whats-bug-how-recognize-them.html
it's 9 pages though.