I have used the NPX Bio pellets before and it did reduce my Nitrates close to 0. But it also pissed off a few corals. My Aussie Leatehr Toadstool and Tyree Leather closed up and didn't want to open up. After running the reactor with the pellets for 2 weeks, I took it down. It took another 2 weeks for the leathers to open up again...
I am tempted to try it again, since it really did take care of Nitrates...but I am afraid it is going to do something along those lines again to some of my corals...
Higor