[fishyfish22]

Got some plants from a lake. I pit some water in the glass cup and now today I see little worms on the glass, they seem to have hairy like things coming from their heads. Too small for pics. Then there are tiny eel things really skinny. Look like underwater pillbugs that are flat. I know the worms are some sort of parasite. What are they?

 

[Kathyy]

Could be anything. Check this thread out, maybe your critters are in it.
http://www.plantedtank.net/forums/shrimp-other-invertebrates/40061-whats-bug-how-recognize-them.html

 

[fishyfish22]

I have a hydra. Are they bad? Really thought it was a killer.

 

[StuBaby]

Hydra are small invertebrates. Their tentacles contain thousands of stinging organelles to paralyze their prey which they then pull into their trunk. They only eat things small enough to fit inside their central tube. So, to answer your question, they are not harmful to fish or plants. They're just a cool additions to your tank if you have a magnifying loop. I would, however, be very concerned about collecting more worrisome types of parasites and bacteria that may be harmful to your tank habitat.

 

[StuBaby]

The worms you describing are most likely planaria. If you have those, you may also have flukes and round worms, and some of those do carry disease, for fish and humans. Be careful!

 

[fishyfish22]

yup. it's planaria. will a saltwater dip kill them? the planaria, i mean. the hydra seem pretty cool. it's like a freshwater anemone.