Help! Over the last couple days I have noticed there are little white worms in my tank! They are about 1/2 long and look like little hairs in the water. What are they? Are They dangerous? Please Help!!

My guess is they are planeria, free swimming parasites that pose no threat to your fish. They are often introduced on plants, or on rocks. Eradicating them often means completely stripping down the tank and filtration which obviously means cycling the tank over again. Try harvesting them by hand and see if you can keep on top of them. I'm not sure if copper-based solutions will kill them, you have to be careful using these become some fish are very susceptible, especially scaleless fish like Loach

i can remember someone coming to me years ago with this problem and i told him to try salt in the water and it worked. He lived near me and he was so grateful he said hed drop me some welsh slate round that hed got from a quarry where his brother worked. I wasn't in when he delivered it and he left it in my driveway. When i got home there was a ton of it. I could probably have tiled a roof with it there was so much. Anyway back to the problem, the salt worked for him as it killed them and then it was just a case of siphoning them out. Im just not sure what the does of salt was so may be someone can let you know a safe dosage level for your Oscars. I think its probably about a tablespoon per gallon. why dont you try siphoning some out and see if the salt kills them

my father had them on his tank. they are harmless but ive heard if u get them, its time to do more water changes. my lfs guy told me that it comes from there waste. my father put a clown loach in and the prob was solved

These little critters thrive really well if you overfeed, try under feeding for a couple of weeks and see if they diminish in population. I suppose the one good side as they are no threat to your fish, they just look unsightly if you got lots of them, very much like snails, (I hate them)

if u got loaches half the salt dosage as 2much salt will kill the loaches

yep, as others say, harmless, unsightly, and can multiply greatly when tank maintenance is needed. A good sign that your O has outgrown your current regimen.

Remember to tear down the filters regularly ... cleaning or replacing the mechanical in tank water, cleaning out the filter housing and the impeller/impeller housing, if you use carbon, up the replacement schedule.

Make sure you are getting the gravel well, enough, should be clear when it comes up. Clean up the algae on the glass (more so they don't start climbing the glass eating algae once you start removing all their other food sources).

Reduce feeding and making sure to remove uneaten food. Check water quality for high nitrates.

A good way to help harvest them out quicker is take some food, anything non-toxic to your O, and put it in a mesh ... the worms will be attracted to it and you will find the food covered in the worms, remove, thow away, repeat.

Those are pretty much all the things I can think of, if one of them fits for you, hope it helps ... if not, know that they are not harmful ... in fact, they are food to other fish, like Bettas.