Controlling pump speed is not something that is essential, the manual pumps set to a speed that gives enough flow is totally fine.
To control pumps with an AQ5 the best way is with the USB d5's ... they are a normal manual control d5 that has been modified so that a digital controller replaces the dial function. They can then be controlled via USB and the Aquasuite software or directly by the AQ5.
The manual pumps can be controlled via voltage using the poweradjust modules but as far as I know the pumps have a limited voltage range so the available speed range of the pump is reduced
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For a flow meter; This one connects directly to the flow port on the Aq5
This one connects via USB to the motherboard and to the Aquabus high port;
For the pressure based models only the 400 has a really useful range;
The lower models max out at under 1 Gallon per minute flow rate which has been shown to be an ideal flow for most loops. The 400 ranges from about 0.3 to 1.5 GPM
The MPS flow meters connect via USB to the motherboard and by aquabus cable to the Aquabus high port.
For water temps the Aq5 can use many types of sensors;
Ones that fit into and plug spare g1/4 ports
Ones that fit between other fittings in the loop
For air temps the AQ5 comes with a few flat ribbon 2 pin sensors that can be positioned in air flow or attached to surfaces. eg; behind a fan to measure incoming air temp.
The USB pumps, poweradjusts and flow sensors come with the USB and aquabus cables needed to use them by themselves.(except the non USB flow meter, it needs its own special 3 pin cable that does not come with for some inexplicable reason)
Because All the devices above connect to the Aquabus high port, one way to do it is to use multiple splitter cables like these
The add on devices come with 3 pin aquabus cables so they can be used while they are connected via USB. They can also be used without the USB connected but to do so the 5V power from the USB cable needs to be replaced. That is what the 4 pin Aquabus cables are for. They are the same as 3 pin aquabus cables but with an added 5v line for power.
There are several diagrams posted in this forum on how everything connects together.