air filter (a car part that filters contaminates out of the air)
NAPA 6033 is a direct replacement for Genrac 059402
check this website partsamerica.com should help u
Depends on tank size. if it's very small and easy to clean-you can just pump in air with an air stone or ornament, but if it's 5 gallons or more and you plan to add more fish, a filter will keep it...
No, they are not.
How to Check Your Car's Air Filter
How to Check Your Air Filter
How to Change an Air Filter
HVAC Air Filter Replacement