ok i noticed a bunch of tunnels along the glass in my substrate in my planted tank. i thought maybe it was from baby snails or something, but decided to take a closer look with a powerful lense that i have and i noticed something moving inside the tunnels. they are like some kinda flatworm is seems like. it's like a tiny white/silver ribbon. now keep in mind these tunnels are only about as big around as a sewing needle. has anyone else ever seen these or know what they may be?