GOD I HAD A MILLION OF THOSE THINGS, I had them everywhere though, even on the glass and rocks...I eventually just got so fed up that I just scraped them off...But I still have some int he sand, some of them are really little and I just see them look like they come nowhere out of the sand, (i probably get 1-3 per second, varying in size), and some of them are large bubbles on the bottom, with algea growing over the top of them...what do we do?