I make my own food for my fish and corals and freeze it, that way I know I dont have any phosphates in it. I throw a frozen cube on the grate of my Tunze nano-stream and let it get slowly shot out. Usually the fish get the first peices that get shot out, and after a while when a large portion of the cube gets shot out it's enough to feed the lps corals. I dont directly spot feed them, but I do have lots of flow so it never falls to the bottom, just stays in suspension until something eats it or it falls into the filter sock which get's changed alot. That's why I can feed heavy but still have no nitrates.