The Pentair Tank Bottom (178743Z) is the OEM replacement lower housing half for POSI-CLEAR RP and System:2 Modular Media Filter cartridge filter systems.
The tank bottom forms the lower half of the filter's pressure vessel, housing the cartridge elements and sealing against the tank top to maintain system pressure during filtration. A cracked, warped, or corroded tank bottom is a common source of housing leaks and requires full replacement rather than repair.
Specifications
| Pentair Part Number |
178743Z |
| Part Name |
Tank Bottom |
| Quantity Included |
Each |
Fits Into
| Brand |
Equipment Line |
Model / Part Number |
Notes |
| Pentair |
System:2 Modular Media Filter |
PLM100 |
Tank bottom for POSI-CLEAR RP filters |
| Pentair |
System:2 Modular Media Filter |
PLM150 |
Tank bottom for POSI-CLEAR RP filters |
| Pentair |
POSI-CLEAR RP Filter |
PXC100 |
Fits all POSI-CLEAR RP filter models |
| Pentair |
POSI-CLEAR RP Filter |
PXC150 |
Fits all POSI-CLEAR RP filter models |
| Pentair |
POSI-CLEAR RP Filter |
PXC200 |
Fits all POSI-CLEAR RP filter models |
Compatibility is based on Pentair parts documentation and available OEM records. This is not an exhaustive list. For certainty, verify the part number in your equipment's manual or on the original part itself before ordering.
Poolaroo Pro Tip
When replacing the tank bottom, inspect the tank top and clamp band together — mismatched wear between the two housing halves is a common cause of recurring pressure-seal leaks after a partial tank repair. Replacing the tank bottom alone will not resolve a leak originating from a worn tank top or clamp band.
