Black Stuff in between sand and glass on tank

[l0ucifer]

I have some black stuff that keeps appearing between my sand and the glass on the tank. I scrape it away and it always comes back. Is this something I should worry about?
Thanks

 

[dougai]

sounds like detritus..
gets some snails they will eat that right up

 

[l0ucifer]

Is it bad that it's there or really just an eye sore? The snails can't really get in and get it.

 

[dougai]

ummm actually it is not that bad for the place that is in... you can move sand around to get in there... its def en eye sore though