What is a 720XT?
I am going to go out on a limb and guess it is an Aquero 5 of one flavor or anouther.
On the bottom of the Equero unit, on the opposite side from Fan 1 there is a three pin connector labled "Tacho". Connect a three wire fan cable from it to your motherboard CPU fan connector. In Aquasuite 2012, under Aquero 5 -> Alarm Configuration select the pump failure or temperature or whatever you want for the computer to shut down for. Select a "Warning" and "Alarm" number for each one.
Then, under Aquero 5 Alarm Actions set up what happens when an alarm or warning occurs. I have the AS2012 set for giving a warning first, which is set to sound the beeper in the Aquero 5 and blink the RED LED in my water tank. The Alarm is set to turn the Tacho signal OFF, buzzer Off and RED LED Blinking.
The key is for an Alarm condition to turn Tacho signal OFF and Warning condition to call your attention but keep Tacho signal ON.
What the heck is a 720XT?

Its the external watercooling kit. A quick google gave me that info! But never used one so cannot help here!

I am an idiot for not looking in the Shop area first.
Connect three wire cable from RPM signal output of slot PCI board to CPU fan on Motherboard.
Set the alrm function to Tacho off in Aquasuite 2012. that should do it.

I don't know if this is related, but I'm having the same "problem." I hooked up my Aquacomputer D5 pump's RPM sensor to the Aquaero 5 PRO on the 3-pin RPM connector, but I don't see anywhere in Aquasuite where I can see what RPM the pump is running at.

<Quote Shoggy>
Overview of all new products from the last days

Friday, July 27th 2012, 10:25am

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After some request for more information about our new products in the aquaero 5 thread I thought it would be nice to sum up all new products of the last few days into one thread.

Unfortunately all software screenshots are in German but the software can be also switched to English.

Let’s go ;-)

Laing D5 pump with USB and aquabus interface
We have developed a new controller board for the D5 pump which also fits directly in its housing. The controller features connectors for USB, aquabus, a temperature sensor and an output for a tacho signal which can be configured – for example it can be turned off when an alarm is active.

The rpm value of the pump is forwarded by USB or aquabus. You can connect up to four of these pumps via aquabus to the aquaero. There is no limit when you use them via USB.

The best part: you can adjust the speed of the pump through the aquasuite 2012 software or the aquaero 5. The controller uses the speed regulation of the pump which is already there so it does not generate any further heat because of an voltage regulator like it would be the case with a poweradjust 2 controller for example.

When you have done all settings you can also unplug it from the USB or aquabus. The controller has its own processor and does not require a permanent connection to the PC or aquaero 5.

<end Quote>
I think you goofed partner. If the 3-pin "RPM Sensor" you are talking about on the Aquero 5 Pro is labled "Tacho", that is an OUTput connector intended for Motherboard Fan headers.

The RPM signal should show up in Aquasuite 2012 under the D5 pump tab.

I would have thought that Warrior1986 has the original version of the pump rather than the new one with USB and aquabus headers but could be wrong.

@Warrior1986 what RPM connector did you hook it up to? To monitor the RPM of a pump you have to just hook it up to one of the fan headers and it just shows up as one of the fans, Aquasuite cannot tell the difference between a fan and a pump if using anything other than the new range of pumps with USB and aquabus headers or the original Aquastream pumps.

Hmm, that's a problem then as I currently have the pump hooked up to the fan header to be able to control the pump speed, and I have no other open fan headers. So then it sounds like I will be unable to monitor the pump's RPM.

Quoted from "Warrior1986"

Hmm, that's a problem then as I currently have the pump hooked up to the fan header to be able to control the pump speed, and I have no other open fan headers. So then it sounds like I will be unable to monitor the pump's RPM.

No, that should work fine, if you say you have the pump connected to a fan header on the Aquaero, it should act just like a normal fan. Check the wires to make sure they are ok and try a differnt fan header.

EDIT: Make sure all 3 wires from the pump go to the same fan header.