Just set this pump up to tumble biopellets in "BR-140 Biopellet Reactor - Reef Octopus" and it is doing a great job. I used the longer suction cup feet, but I could still hear the hum or vibration. So I set it on a section of Oxo mat that is sold at BRS to quite pumps and that reduced it further. It's only been running a day, but I expect/hope it gets quieter over the next couple of weeks. Overall I'm pleased with my purchase so far. Ehiem might be quieter, but not by much.

I had received the pump and due to my negligence, I forgot to make sure the impeller was secure. It had ended up causing the impeller to snap off as it was running, freely shaking within the chasis, scratching the pump's insides, heating the pump up and causing irreparable damage. I contacted BRS, expected to have to cash in for a replacement. To my surprise, BRS sent me one free, and I sent mine back some time later. This pump is incredibly powerful, silent, and robust. Just ensure that the impeller is nice and snug before operation! (as with any pump, for that matter)

I have used Eheim 1260 pumps for years in my living room tank, but I could always hear the low vibration from my bedroom directly above. So when setting up a new Reefer 250, I decided to look for a quieter pump.

Syncras have a good reputation, but I read some rumblings that the larger models were not terribly quiet. I took a chance on the 4.0 model, and I am really glad I did. Once I mounted the (very long) suction cup legs to the pump, and let the pump break in for a few days, I would estimate that the Syncra makes only 25% the noise that the Eheim 1260 did. I would not call it silent, but it is extremely quiet, even when restricted. I cannot hear it from my bedroom anymore.

Time will tell regarding reliability, but for now, my old 1260 pumps will serve as backup.

Best overall pump i've had to date. Just Superquiet and very nice adjustment dial instead of haveing to adjust a valve. Love it!

Nice and quiet, works great.

Product arrived on time and well packaged. Does a great job for what I need.

Excellent pump, super silent, and powerful. I have four Sicce pumps now and would recommend them to anyone looking for a reliable and silent pump.

I use this as a return pump from the sump. It's quiet and has a super voluum of water. I turn it down most of the way using the built in control.

This pump can move water. I have it as a return pump in my sump for a 90 gallon tank and the ripples it creates is awesome.

Have this as a return pump on my 93 cube and it's amazing. I have it open to the lowest setting and it still adds to the water movement in the main tank

This pump is super quiet. It comes with 2 sets of feet; 1 with suction cups and the other rubber nubs. The flow rate is adjustable. I have it fully pegged on my 120 gallon and it is silent. Ive had an Eheim in the past and I think this is more quiet.

Was looking for the strong silent type and scored on both! Powerful little pump that barely makes a sound!