Very cool.
Some Q's for ya ...
Are the outputs we see there, the sump return, or is that a closed loop? Or one of each?
I can't quite tell from the picture, but does each successive downstream outlet extend a little further into the tank (stepped up from the previous)?
What are the outlets, is that loc-line or did you just use a bunch of 90's? Is each nozzle aimable?
What kind of sump turnover do you have? What did you do for a sump? How do you deal with microbubbles, do you have dams and baffles or did you go with a raceway?
How long did the tank have to sit empty to let the silicone cure? Was 24hrs enough or did you go with longer?