Little white worm/snake looking thing?

Question

is swimming around in my aquarium, he is about 1cm long and I see him occasionally, he is tiny.

What is it? how did it get there and is it bad? I also have snails, they probably came in with plants I bought.

I have a 120l freshwater aquarium with angelfish guppies and tetras.

he swims exactly like a snake would, head first with tail moving like a snakes does.

definitely not midge larvae..

Answer 1

The "worm" may be just that - a harmless nematode that lives in the gravel. Every tank has a few, but yours may be overpopulating if there are a lot. If they're large enough that you can see them, it's doubtful that they are a parasitic form. They may also be the larvae of a small fly (midge). These are a flying insect that lays it's eggs in the water and the larvae are aquatic. In either case, these can't survive in large numbers without a food source. So you may be experiencing a buildup of organic waste in your gravel (which the worms are feeding on) if you see a lot of these.

nematode photo: http://www.microscopy-uk.org.uk/micropolitan/fresh/other/nematode2.jpg - smooth body pointed at both ends; swims in a "shivering" motion

midge larvae photo: http://www.benthos.org/Education/SlideLibrary/Shadows/035-Chironomidae.jpg - constrictions along the body and a definite head; swims by whipping body back and forth in an "S" shape

http://aquarium-answers.blogspot.com/2007/03/trematodes-and-nematodes-in-fish.html - some other info and photos

Answer 2

Sounds like a nematode. Most fish will eat them. They are harmless; however, they are usually an indication of high nitrate levels in your tank, so make sure you aren't overfeeding and that you are doing water changes regularly.

Answer 3

Those are Nematodes....Nematodes. I like those little critters, they are cute to me. Don't worry, its harmless.

CC

Answer 4

it is a baby guppie fish