^ What do you mean by modded it? Also, do they come with the same computer type controller that the vortech comes with or do you have to buy a separate controller?
Basically, the Tunze Streams feature a front volute that acts both as the site for suction and output. When I modded mine, I basically cut some of the strips of plastic that act as the filter grating (since what limits the flow on these pumps is the amount of water reaching the propeller). I also cut down the effluent nozzle to spread the flow out. Works great on my 40 BR. Here's a short vid where you can see it going: http://s188.photobucket.com/albums/z107/Amphiprion_photos/?action=view¤t=tunze001.flv