When you over tighten the clips you can easily break the plastic barrel at the bottom of the nut making the filter leak as its not being held together properly. A full set of new parts from the manufacturer to replace all 8 will set you back around £120 as they are £15each rrp.

Our Compatible with Fluval FX4, FX5, FX6 canister clips come with new stainless steel bolts and nuts too so you only need to re use the plastic knob from your original. 

You will receive the 8 parts shown in the first photo to enable you to reuse the nut knobs off the originals fittings.