CHEZURAquarium decisions A magnetic rotor depends on a clean well and intact supports. One grain can create chatter, seizure or wear.
Look for cracks, distorted blades, scored shaft and missing end bushes. Descale only with material-compatible methods and thorough rinsing.
Hair and fibres wind around the shaft and add drag even when hand rotation seems possible.
Seat bushes, close without pinching and purge air. Persistent noise after air clears means stop.
Compare performance only under installed wet conditions.
| Situation | What to do | Why |
|---|---|---|
| Hum but no flow | Disconnect and inspect rotor | It may be seized |
| Rattle after sand | Clean well and shaft | Grit changes support |
| Broken blade | Fit exact rotor | Imbalance causes vibration |
After disconnect and inspect rotor, measure or observe Hum but no flow again with the same method. Record Random lubricant does not repair damage. as well; if neither changes as expected, revisit the diagnosis before adding another intervention.
Sources include institutions, technical studies and manufacturers. Chezur separates established mechanisms from editorial decisions for home aquariums.