heres an interesting article,note i have even more flow/pressure than a stock one,
The Hydor (Seltz) L30 II pump lived up to the advertised claims and in fact exceeded my expectations in several areas. I found the pump to be well made and quite easy to install, thanks to its compact size.
The Hydor L30 II produced excellent head pressure and flow for a pond pump of its size. Its performance closely matched that of the popular Eheim 1250 but it is closer in size to the Eheim 1048. The L30 was quiet during normal operation and the motor only became slightly warm to the touch while operating 24/7.
The extra head pressure generated by the Hydor L30 II will offer a slight advantage in cooling systems using one of the more restricted flow waterblocks incorporating micro-channels and/or jet impingement. (Remember, it takes pressure to overcome flow resistance and generate flow.)
Overall, I found the Hydor (Seltz) L30 II to be an excellent pump and I highly recommend it to anyone seeking a medium to high-performance pump for his or her PC water-cooling system. With a street price of under $50 US, this pump deserves a serious look. A big thanks to our friends at Crazy PC for sending us the pump to review! Check out their website for everything cool.
For DC powered pumps, I monitor the electrical noise (mV p-p) present on the +3.3V. +5V and +12V DC rails of the computer with an Oscilloscope while operating with, and without, the pump powered on. In some cases a 12 VDC powered pump can induce a lot of noise, especially onto the 12V rail. In general, AC powered pumps don’t create any problems.
Hydor (Seltz) L30 II pump: NA (AC line powered