I started up a tank about a month ago and use flourite as the substrate i usually use eco-complete so i juts noticed this. I have a magnet glass cleaner which i am using until i gets some ottos for the new tank but i was running it across the glass close to the bottom and notice that some of the pieces of flourite were jumping up to the magnet. I new it had some iron in it but i didn't think it would be enough to jump up that much. Just something interesting i thought i would share.
Texas A&M-Commerce Track & Field