Purelyh2o.com highly recommends NP Active pearls
These bio pellets are a must have, especially if you have a heavily-stocked reef aquarium. They're the perfect shape for tumbling and since they're certified marine biodegradable, they're perfect for a reef tank with expensive livestock. After a few weeks of using Dr. Tim's BioPellets, we've attained zero phosphates and nitrates, even with a big bioload and heavy feeding. You'll notice the water and glass will clear of green algae and the coral tank will grow different shades of coralline. Purely H2o.com highly recommends NP-Active Pearls to all marine aquarium hobbyists!
Reviewed by: PurelyH20.com from South Daytona, Florida on 3/25/2015