Dark green stuff on fish tank filter?

perfectly normal. it will NOT harm your fishes :)

that green stuff is algae. it's harmless. my dad bought like some mini snails and shrimp and it was clean enough.

It's algae, usually harmless. Just give it an extra scrub when you check and clean out the filter. If too much grows it can clog up the filter.

Ian

It's algae, Get some snails and catfish to eat the stuff naturally

Its algae. If you feed your fish flakes, there might some of that there too. Its harmless, but if you don't like it, get a pleco, it'll eat it. You should also change the sponges.

Yes, it's safe but the filter may not work as well. Here:

http://freshaquarium.about.com/od/algae/a/attackal...

Its algae get a snail to eat it its normal

It's algae. It's normal. You should buy a pleco. They eat that stuff.

Its alage, its happens to my fish tank, its fine. to get rid of it just give it an nice was and rub it with a brush and it will go away. Do not forget to clean your tank every week!

Its algae, if your tank is big enough, get a pleco.

Its algae.

Get a Placo and some goo-gone. The goo-gone is really great at removing this crap. :D