C182 PLT ON RNAV GPS 23 APCH RECEIVED LOW ALT ALERT FROM TWR CAUSING A DISTR WHEN ALTS WERE IN COMPLIANCE WITH PROC.

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FLYING THE RNAV (GPS) 23 APCH INTO GON. HAD CONTACTED TWR. PASSED FAF AT ABOUT 2100 FT MSL AND BEGAN DSCNT TO INTERMEDIATE STEPDOWN FIX ZEMAP WHICH MUST BE CROSSED AT OR ABOVE 800 FT MSL. ABOUT 1 NM BEFORE ZEMAP DSNDING THROUGH 900 FT MSL AS I WAS BEGINNING TO ARREST MY DSCNT CTLR STATED: 'LOW ALT ALERT. CHK ALT IMMEDIATELY. ALTIMETER 30.14 INCHES.' MY ALT WAS IN ACCORDANCE WITH THE IAP. MY ALTIMETER WAS SET CORRECTLY. AT THAT MOMENT THE ISSUED LOW ALT ALERT WAS POTENTIALLY HARMFUL BECAUSE IT DIVERTED MY ATTN FROM SMOOTHLY ARRESTING MY DSCNT AND PROPERLY NOTING PASSING OF ZEMAP. IT TENDED TO PUT ME 'BEHIND THE AIRPLANE.' I INFORMED THE CTLR THAT MY ALT WAS CORRECT AND CONTINUED THE APCH. AFTER LNDG; I QUERIED THE CTLR AND HE INFORMED ME THAT THEIR EQUIP HAD BEEN INDICATING MANY LOW ALT ALERTS ON THE RWY 23 APCH AND THAT THEY WERE REQUIRED TO ISSUE THEM TO THE PLT. I AGREED THAT THE CTLR HAD CERTAINLY ACTED PROPERLY. AS I WAS ENTERING MY IFR CLRNC FOR THE NEXT LEG OF MY FLT INTO MY GPS SYS; I HEARD THE TWR ISSUE YET ANOTHER LOW ALT ALERT TO AN INBOUND ACFT ON THE RWY 23 APCH. I BELIEVE THAT THE PARAMETERS PROGRAMMED INTO THE LOW ALT ALERT SYS FOR RWY 23 AT GON SHOULD BE REVIEWED AND FINE-TUNED TO MINIMIZE THE OCCURRENCE OF SPURIOUS ALERTS.