Big thanks to CRW for coming over and having a look at everything!  Thanks for tolerating the house in disarray, kids racing around, and unexpectedly having to jet to boyscouts.  
I love your idea, and am trying to hone in the how to make it work.  I thought maybe everyone here could have a look and give thier 2 cents.  
 
His Idea was to use the 150 as a sump/fuge with no baffles, and plumb a smaller sump for the skimmer downstream.  I drew the following diagram, and if we can figure out the backflow for water if the pump goes out, this would be a setup I could have up and running the quickest.
 
 
If I use the overflows from the 150, the 150 will be mostly full of water.  So the DT, will drain to it, and keep it overflowing 40-50 gal (if cal is correct??) which would continue to flow into the second sump and that would overflow.  However, What if I used 2 smaller sumps downstream one to catch each of the 150 overflows, and let them both Y into the return pump.  That should give me the 40-50 extra gallons of space for the DT?  The 150 has teeth right at the top, so it won't drain more than an inch or so.  I suppose really this would just be some more space for backflow, but could house doseing, ato, and future reactors?
 
Would this work?  [attachment=61017:name]