(Sizing Guide). Features built in temperature controller with digital display, titanium heat exchanger, black ABS cover, and a 2-year warranty. Unit produces some of the lowest noise and vibration levels of any chiller on the market. Recommended Flow Rate: 240 gph. Input/Output: 1/2", 5/8", 3/4" INS (Hose Barb). Using either an existing pump or an additional pump, water is circulated through the chiller, cooled, and returned to the aquarium or filter system. All models are safe for use in either salt or fresh water. For additional information, please visit the JBJ Lighting web site. Free powerhead with each if requested in the note section. Limited quantities