Replacement Air Filter for Airmax KoiAir KA40, 2-Pack
The intake filter on the KA40 aerator keeps dust and debris out of the compressor diaphragm. When this filter clogs, the compressor works harder, dissolved oxygen output drops, and the diaphragm wears out faster. A plugged filter is the most common preventable cause of reduced aeration performance. This 2-pack covers the KA40 for a full year, or two replacement cycles in particularly dirty environments.
| Compatible With | Airmax KoiAir KA40 aerator |
|---|---|
| Quantity | 2 filters |
| Replacement Frequency | Every 6 to 12 months; more often in dusty or high-pollen environments |
How to Replace
Unplug the aerator before servicing. Remove and discard the existing filter without attempting to clean it. Insert the new filter into the intake housing. Restart and check output at the diffuser to confirm airflow has improved. If output remains low after a new filter, check the diaphragm and diffuser for wear.
Fits the Airmax KoiAir KA40 aerator only. Keeping filters replaced annually is the single most cost-effective maintenance step for extending compressor life.

