BioCube 32 return pump rattles

[Barry_Cuda]

I'm cycling a brand-new Biocube 32 and although the pump noise itself isn't excessive, there's a background rattle when the pump is operating that I find annoying. Has anyone else encountered this and hopefully found a way to reduce the rattling? I suppose I could replace the pump but I'm not eager to do this right off the bat, especially since there's no guarantee a new pump would be any quieter.

 

[Alex F]

Check to see if it's rattling against the wall.

I found mine doing that just a bit.
It really amplifies the sound.

I cushioned it by wedging suction cups in between.

 

[Barry_Cuda]

That's worth checking. Although the sound I'm really bothered by isn't what I'd call the regular noise of the pump running... it's more of an irregular-yet-constant rattling noise. It almost sounds like there's some sand in the impeller mechanism or something, but it seems unlikely that any noticeable sand particles would have gotten past the filter floss in chamber 2 and made it all the way to the pump. I guess there's nothing to be lost by pulling the pump out and giving it a cleaning ahead of the regular maintenance schedule.

 

[Barry_Cuda]

Well, I found the problem, but there isn't much I can do about it right now. The little plastic bracket that holds the suction cups on the bottom of the pump wasn't fully locked into place. I pulled the pump and ran it in a bucket of water... still rattling. Fixed the loose bracket - no rattle. Reinstalled the pump - back to rattling again. I don't really feel like futzing around with it further at this point, so I guess I'm just going to tolerate the noise for now.