Currently, Polygroup has two generations of pump filtration systems being sold 2015 and later.  Both filtration system generations are excellent products but they are different in general concept.  The primary difference between the two generations is submerged versus non-submerged pump system.

Side Mounted

SFS Filtration System	SFX Filtration System

 The SFS Filtration system uses a non-submerged system where the pump is located at the bottom of a filter canister locked in place by a retaining nut.  The SFX Filtration system also places the pump at the bottom of filter canister but the pump itself is inside the canister submerged, locked in place by a motor seal nut.  The SFX Filtration System pump runs cooler and quieter because it is submerged in water. 

The SFS Filtration System is louder than the SFX but the removal of the pump is a little easier. The SFS Filter System utilizes a square hole in liner to mount the filter system, while the SFX filter system utilizes a round hole in the liner.   However, there is a SFX adapter kit can allow a newer SFX Filtration System to be mounted on an older pool. See link to the adapter here.   There is also a difference in the watts and amps used by the two generations of side mounted filtration systems.

 Free Standing

RP Filtration System	RX Filtration System

 The RP Filtration System and RX Filtration System are the ground mounted filtration systems of the two generations of Polygroup Products.  As with the SFX and SFS Filtration systems, the RP and RX Filtration systems are a submerged versus non-submerged pump filtration systems.  Both are excellent products capable of meeting your needs.  The RP and RX Filtration Systems can be used on old or new quick set pools.  However, a pump for a RP system will not fit in a RX system.  The same can be said for the SFX and SFS, the pumps for each system are not interchangeable. Below are the differences in watts and amperage between the two generations of ground mounted filtration systems. 

If you have any further questions please contact Polygroup at 1-888-919-0070.