Hi.
You need the pumps connected via 4 pin aquabus cable so they can be assigned to a controller on the Aquero. They won't show up just using USB.
here is mine, you can see on the second controller it shows as mps D5. you can connect up to 4 by giving them each a different aquabus address. You also need to change the priority from USB to aquabus on the D5 config tab. On mine the default address is 12 and can be changed to 12,13,14,or 15.