worm like creatures

Question
HI WE HAVE A 30 GAL. TANK. WE WERE CLEANNG THE GLASS AND MOVED SOME GRAVEL AND NOTICED SOME LIGHT BROWN WORM LIKE THINGS AND OUR SCISSOR TAIL FISH STARTED EATING THEM...WILL THIS HARM OUR FISH?

Answer
Hi Regine
Those are most likely nematodes, and they're harmless to you and the fish.  They usually live down in the gravel, and come out at night when the lights are off, or if the gravel is stirred.  When they swim, they look like a thin hair, and have an S shape to them.  Some fish will also eat them, which is fine.  Usually they'll multiply in tanks where the fish are overfed(lots of leftover food on the bottom), so cut back on the amount of food you're feeding, and be sure to do weekly water changes/gravel vacuums.

Hope that helps :)

Christy