Your D5 pump should be regulated off the small red/white/blue dial located at the base of the pump(if it's mounted upright) and the single (yellow) RPM wire is for monitoring your pumps RPM but is unable to regulate the pumps speed unless you have something like this
coming from your pump's end...? Whereby two wires are for PWM and the remaining two wires are for power from PSU. In the latter case the dial is missing from the pump as the pumps speed will be regulated in BIOS via a fan curve/profile. You could double check with us to see if your pump is capable of being controlled by a fan controller or a motherboard fan header.
If you're looking towards running off multiple PWM fans as well as a pump that has PWM(mind you without the dial) then you should look into the
Swiftech PWM splitter and otherwise a 5.25" front panel mounted fan controller meant for any enthusiast watercooler is the Lamptron's FC 5 v2 as well any other fan controller currently made by Lamptron.