We have filled the tank for a fresh water test. Found a couple of leaks but nothing major this time.
One is a solvent welded joint... out of close to 300 joints - 1 is not too bad ey?
The return pump has some very good flow and is as quiet as I expected.
The overflow is silent without any bubbles and the siphon restarts automatically.
The CL pumps are a bit louder than I expected, but I have read that they are quieter after running them in for a few days as the bearing oil disperses.
Otherwise, I am confident the insulating of the cabinet will keep the noise down.
One of the Hammerheads had a broken fan.
Reeflo are sending a new fan, but I will tell you, the noise it made was very scary!!
I thought it was about to explode! But at least it was just the fan and not the motor/bearings.
Here are some more photos
Fill her up!
Just the return pump running, we have taken out the CL to seal the connections tomorrow.
This is the overflow at the moment.
We have turned the aqua-medic comb upside-down to create a combless weir and the water height in the tank is perfect.
The overflow box is working perfectly and the ball valves are easy to tune making the overflow silent.
There is a fair bit of flow through the sump over the baffle, it makes a very small amount of noise.
Once we tee the return to the chiller, the flow will be reduced a bit.
We spent the afternoon mounting the light ballasts and finishing off the timer setup.
The ballasts fit snugly up under the stand above the power panels.
Trish has re-done the aquascape totally! She has used the exact same rocks + 1 rock.
It is more lagoon/low profile, and has more hiding holes/caves I think. Looks good and hides the outlets better than before.

It is hard to get good photos of the new aquascape, but here it is from the right.