Bubble Magus SP4000 Replacement Impeller Bubble Magus SP4000 Replacement Impeller is a replacement needle wheel impeller for the SP4000 pump used with the Bubble Magus Curve 9 Protein Skimmer. This is for the SP4000 pump and should not be assumed to fit DSP4000 pump applications. SP4000 Needle Wheel Impeller Compatibility Replacement needle wheel impeller for the Bubble Magus SP4000 pump. Compatible with the Bubble Magus Curve 9 Protein Skimmer. Useful when the original impeller is worn, damaged, noisy, or no longer spinning correctly. Pump body is not included. SP4000 Impeller Service Notes Disconnect power before servicing the pump. Remove the pump cover, take out the old impeller, clean the impeller chamber, and install the replacement impeller carefully. Restart the skimmer and confirm that the pump runs smoothly with stable bubble production. What's Included One Bubble Magus SP4000 Replacement Needle Wheel Impeller.