Just saw this on another forum and I thought it would be nice to share.
Reef BioFuel
Helps maintain a balanced nutrient-limited marine aquarium by enabling the hobbyist to enhance the rate of microbial growth and reproduction, increasing the rate of phosphate-reduction and denitrification; this is of particular benefit in heavily-stocked, well-fed reef aquaria. For $12 I decided to give it a try so I ordered one. I will let you guys know how this works out.