The Fluval FX5 & FX6 Motor Unit is the genuine replacement motor unit for the FX5 and FX6 High Performance Filters — the part to fit when a filter has stopped rather than merely slowed.

Key Features

• Made for the FX5 and FX6 High Performance Filters
• A complete motor unit rather than a rebuild, which is the right answer when the motor itself has failed
• Genuine part, so it seats correctly and the seal faces match
• Made by Fluval, the aquatics brand of Rolf C. Hagen, which has been building aquarium filters since 1975

Fitting It

• Unplug anything electrical before putting your hands in the tank
• Disconnect the hoses and take the unit to a sink rather than working over the tank
• Check the old part against the new one before fitting. If they differ, stop and check the model number
• A smear of silicone lubricant on an O-ring before reassembly makes the next service much easier and helps the seal sit properly
• Prime the filter and watch the first few minutes of running for leaks before you walk away

Good To Know

• This is an expensive part. Before ordering, rule out the cheap causes: a blocked strainer, a clogged foam, a fouled impeller or a perished seal ring
• A motor that hums but does not move water usually has a seized or broken impeller, which is a much cheaper part
• A motor that is completely dead, or that trips the electrics, is the case for this part
• A genuine Fluval spare part. Check the model number against your unit before ordering — Fluval part numbers look alike and do not cross over between series
• Fluval sells these individually so a filter can be repaired rather than replaced, which is usually the cheaper and greener option
• Keeping a spare impeller and O-ring in the cupboard saves a tank when something fails on a weekend