my booster circuit is pretty simple....

It's basicly the same as in this thread (watchout, german language )

It uses this OpAmp ( Datasheet )

The connections:

"+Vs" is 12V supply from the PSU
"-Vs" is ground from PSU
"Output" goes to the Pump or fans
"non-Inverting Input" is connected to the Aquaero
"inverting Input" is connected to "Output"

Theres some things to consider:

With 12V Supply and Aquaero Fan Voltage at max, the OpAmp gives ~11,5V
With an Laing DDC+ connected to the Output, you better attach a *** big Heatsink, because this thing gets quite hot