Topic: What are these?

[polypteridae]

I checked out both stickies.  I even registered and posted this on plantedtank.net and someone suggested they be bloodworms but i don't think so.

Its a 5.5 gallon.  I am doing a fishless cycle with it.  Its been running for 4 weeks.  2 weeks ago i bought some java fern.  Water is half distilled, half well water.  Decor includes new gravel, a small piece of carved rainbow, and mopani wood.  They had to have come in on the java fern, yet the tank that i got the java fern out of does not have these things.  They live in these little green tubes all over the tank, on the walls, decor, plant, rock, gravel.  They have segments but i never see them stray from the tubes, i think they are eating the algae.

Here is the best pic i could get.  They were half out of their tubes but went back in when the flash went off.

[Morgrid]

They look like they might be a species of glassworm.

[Clint]

I agree, I think they are bloodworms or a close relative. They are harmless to your plants and should make good food for your fish.

[jclee]

Bloodworms are midge larvae, so I don't think they're related to them; I'm really not sure. In the pictures of glassworms I found, the worms seemed more transparent and tiny.  I bet, either way, once you get your fish, they'll become a tasty snack.  Have you tried taking one out and picking it out of its casing to check if it's definitely a worm, or maybe an insect?