Cad Lights NR-1 Nano Reactor for Aquariums, 50-Gallon Incredibly small footprint at only 25" diameter to fit in your Nano reef aquariums Effectively help control and remove nitrates; phosphates; slime algae and other algae Compatible with bio-pellets; GFO or Carbon Dimensions: 25" x 25" x 12" Can be hung inside your aquarium/sump; or be installed fully submersed