I've got this little white wiggling threads floating in my tank, a pretty good amount. Any idea what these things are? If thyre a little nasty b******ds how do I kill em?

might be nematodes.

http://www.ucmp.berkeley.edu/phyla/ecdysoz.../nematodesm.jpg

round worms or Nematodes represent about 10,000 species of free-living and parasitic forms. they range in size from a few mm. to 2 cm. in aquarium species. some Nematodes are parasitic on fish and can be extremely difficult to erradicate. Camallanus is an example.

if these 'worms' are parasites, antihelminthic drugs are the only way to rid a tank of these -- disinfecting aquariums will do no good, as nematode eggs can be quite resistant to environmental chemicals. many nematode species have free living young and thus seeing them on the tank walls is possible. while they are not usually mistaken for flatworms, some species of both are extremely small and are therefor difficult to differentiate with the naked eye.

treating for nematodes includes use of one of the following drugs in order of most dependable in my opinion:

Fenbendazole either as a bath or in food. As a bath, it is used at 2 mg/l (7.6 mg/gal) once a week for three weeks. If you can get it into feed at 0.25 to 0.5%, you can feed this food as 1% of body weight per day.

Levamisole HCl (Levisol or Tramisol) can also be
fed in food or used as a bath. Use 10 mg Levamisol HCl per liter (38 mg/gal).

Piperazine sulfate 17% (Agrilabs) or Pipfuge 34% (Butler) is fed at 1% of body wt/day for three days.

other nematodes are not parasitic on fish, but are representative of over feeding, as they set up shop in the gravel and prosper while feeding on the uneaten and decaying food.

to rid the tank of these, gravel vacuuming weekly and stop overfeeding will help.

in your 'threads' are not nematodes, they might be planaria.

http://www.ucmp.berkeley.edu/platyhelminth...s/dugesiasm.jpg

these "Flatworms" are unsegmented and bilaterally symmetrical. they typically appear as small white "worms" seen crawling all over the glass and ornaments, especially at night.

Planaria commonly show up in tanks with an excess of food and most are introduced to an aquarium from other aquaria with live foods like black worms, live plants, or anything else moved from an active aquarium that has them. There is some belief that they can survive in freeze-dried or frozen foods. If a lot of residual food is left in a tank, including dead and dying fish, snails, other animals, and plants, then a few planaria may divide into hundreds very quickly. they usually reproduce by asexual fission.

If a tank is found to have planaria, they can be controlled by a good vacuuming of the gravel and better tank maintenance. to remove planaria from a more heavily infested tank:

1. Set out bait like meat in a mesh bag. remove the bait a few hours after the lights go out on the tank. it should be covered with planaria. throw away and repeat until the population goes down.

2. add planaria eating fish to the tank. such species include the paradise fish, betta, pelvicachromis pulcher and many species of gourami

3. vacuum the gravel very well and do a 50% water change. often, planaria proliferate when the tank is too dirty. this will remove not only some planaria but their food source as well.

4. reduce the foods added to the tank. planaria often proliferate if too much excess food is provided.

5. As a last resource, tear down the tank.

note that Planaria will eat dead fish, fish eggs, and immobile fish larvae (fry newly hatched). they do not pose any risk to mobile fry or adult fish.

Ok well that all sounds very scary! Are any of this nastys harmfull to people? Over all it seems that thyre more of an annoyance then a problem to the fish.

mostly an annoyance. there are fish such as paradise fish that will eat planaria and these are not parasitic to fish in any event.

unless your fish have canallanus, nematodes are similarly not a problem in your tank.

that said though, these critters in sufficient numbers that you see them about the tank indicate that your overfeeding pretty heavily or there'd not be enough residual food for them to thrive in the gravel.

i'd clean up that gravel and get rid of the critters or your water quality will soon be negatively impacted and in turn, your fish.

looks like i got them now too... and the overfeeding part sounds pretty accurate, to be honest. so what now? lots of water changes?

Little less feeding and more water changes and gravel vacs should get rid of them. I've had them a few times and they go away in about a week or two.