My dual D5 NEXT pumps running in series are mounted to a front vertical reservoir. I suspect this is one reason why they’re quite prominent sounding on my system at anything over 30-35%.

Interestingly I tried running them at 50% as part of some cooling testing and the difference in water temperatures and component temperatures seemed basically identical to when running them in ‘silent’ mode at 15-20%. Although I haven’t pushed any overclocks as of yet.

In relation to the above point, my next port of call is to measure the flow through the pumps: why is a low pump speed and a higher pump speed basically achieving the same cooling, and how does flow come into the equation on my system. But right now neither D5 is providing any flow rate data to aquasuite. both pumps are running a usb and aquabus cable to the hubby and aquaero respectively. Not sure why they’re not reporting, can’t figure it out. I was going to put a flow sensor in the loop but didn’t in the end as I had thought the D5s would be reporting this.

My system is arguably fairly restrictive, with three rads, quite a few 90 degrees angle fittings, however, have read that so-called ‘restrictive’ layouts are not a major issue in that water just flows ultimately. But need to get to the bottom of the flow rate measurements.

Thanks Taubenhaucher. Just realised I need to calibrate the pumps first. Which means I need to do the ‘pinch tube’ move then run the calibration. Aquasuite says to pinch tube then run the calibration. But surely I would need to pinch the tube during calibration to give the calibration a ‘zero’ reading?