Gland drains in split case pumps cause more damage than you would expect. A poor drain or blocked drain will cause the gland well to fill with water and penetrate the bearing housing. The water will mix with the grease and eventually cause pitting and premature failure of the pump bearings. The recommended grease is Shell Gadus S2 V100 3 (very good performance up to +130*C, resulting in longer bearing life).
Good house keeping:
Keeping pipework unblocked
Gland well cleaned out and free from dirt
Pump packing adjustment satisfactory
6 monthly inspection of pump non drive end bearing