Volenti - one of the coolest cases I've ever seen. Well done mate.
Brad - in parallel, I'd need a dedicated pump to run them in series, and that would also mean the second bong would have cooler water in it, so deltaT between water and air would be less, evaporation less, and so less cooling (I think).
Cyco-Dude - you're right I DO need to clean it all up, but I'm still building it

This rig is a great base for doing reviews and comparisons. The heater core is awaiting the arrival of a DEEP rad from
CoolHardware for a review. The review should be complete by the weekend if Jess gets me the rad for Thursday.
Will 2 bongs be worth it. Dunno, but I will soon. I will do direct performance comparisons. Simply by turning a tap on/off I can switch units in and out easily.
Marco - overall height is (reaches for tape measure) 7'4" or 223cm, water head is 6'4" or 192cm.
Is it worth it? Do I care, I'm having fun

But I do have 3 pootas I want to water cool. Glad you like it, thanks for the comments.