Generally you should rebuild your pond aerator compressor unit every 3-5 years under normal conditions.  Air filters should be changed or cleaned once or twice a year. 

Pond Aeration Rebuild Kits & Filters

Stratus SRC series "Gen 2" rocking piston compressors are specifically designed for the demanding job of 24 hour...
DC22, DC12  Repair Kits If your air compressor runs but does not pump air after a couple years...
ERP rocking piston compressors contain these wearable internal components. Like tires on your car, these parts need to...
Gast Rotary Vane Compressos are long lasting and continuous duty compressors that hve less depth capabilities than the rocking...
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