Fluval Aquaclear Hang on Filter Impeller AC110
Fits
AquaClear 110 (was 500)
Part no.
A638
Fluval Aquaclear Hang on Filter Impeller AC110
The magnetic impeller that spins the AquaClear 110's motor – genuine Fluval part A638. If the AC110 has gone quiet, is running but pushing little or no water, or is making a grinding or rattling noise, a worn or cracked impeller is the most common cause, and it's a five-minute swap without tools.
Will it fit my filter?
Part A638 fits the Fluval AquaClear 110 power filter only – also sold historically as the AquaClear 500 (the same unit under its older GPH-based name). It does not fit the AC20, AC30, AC50 or AC70; those use the smaller shared impeller built into the AC20/30/50/70 motor unit. Check the filter's model badge or box before ordering – AC110 and AC70 housings look similar but the impellers are not interchangeable.
Specifications
| Spec | Detail |
|---|---|
| Genuine part number | A638 |
| Fits | Fluval AquaClear 110 / AquaClear 500 |
| Type | Magnetic impeller assembly, complete with shaft |
What's included
- One complete magnetic impeller and shaft assembly
Symptoms this part fixes
- Motor runs but little or no water is being pumped
- Grinding, rattling or buzzing noise from the motor housing
- Visible cracks, chips or wear on the impeller fins or shaft
Fitting
No tools required. Unplug the filter, lift the motor housing off the filter case, slide out the old impeller and shaft, and press the new assembly in until it seats. Prime and check for flow before leaving the tank unattended.
Not included
This is the impeller only – it doesn't include the motor housing, filter case or media. If the motor itself has failed, rather than just the impeller, see the AC110 motor unit instead.
Common questions
How do I know if I need the impeller or the whole motor?
If the motor hums or the impeller spins freely by hand but water flow is weak or the fins look worn, the impeller (A638) is usually the fix. If the motor doesn't hum or spin at all, the motor unit itself has likely failed.
Does this fit the AquaClear 70?
No. The AC70 uses a smaller impeller supplied inside the AC20/30/50/70 motor unit – A638 is sized for the AC110 only.
Is this a genuine Fluval part?
Yes, A638 is Fluval/Hagen's own part number for this component, not a generic equivalent.
