The overflow box effectively transports aquarium water to under cabinet sumps, refugiums, or wet/dry filters.  These high quality overflow boxes features bulkhead fittings for secure and convenient installation. The U-tube style compact overflow...

Complete overflow system complete with: anti-clogging and easily removable suction grid; directional water jet; hoses*. Rated for upwards of 660 gallons per hour! It can be installed in aquariums with external sump filter and two drain holes. Xaqua...

Item # 89234 Model Compatibility Power Flow - All Models ID  about 1”. OD of the small is 2” 

ID about 1”. OD of the large is 3”

Box says freshwater, it's the exact same version as the regular one, just with a green label. Complete overflow system complete with: anti-clogging and easily removable suction grid; directional water jet; hoses*. Rated for upwards of 660 gallons per...