Rena air pumps offer you power, silence and versatility in one attractive package. These pumps maintain optimum flow, even in the deepest of aquariums and are so quiet that they can be used in any room in the house – even the bedroom!Unique construction of the Rena Air pumps reduces vibrations and residual noises: less than 30 dB at a distance of 1 meter. Fitting of base to casing guarantees soundproofing. Special extension chambers (Rena Air 200 to 400) absorb vibrations and reduce noise from valves.Model 50: Ideal for depths up to 12", tanks up to 10 gallonsModel 100: Ideal for depths up to 18", tanks up to 20 gallonsModel 200: Ideal for depths up to 24", tanks up to 30 gallonsModel 300: Ideal for depths up to 36", tanks up to 75 gallonsModel 400: Ideal for depths up to 48", tanks up to 150 gallons- Model 300 comes with airstone, tubing and check valve- Model 400 comes with pyramid regulator stone, check valve, tubing and "Y" connector