Im looking for a skimmer and space is seriously tight, i need a skimmer thats no wider then 6 1/4''
any suggestions, i was looking at the tunze nano 9002 but the reviews on some of the internet stores was extremely mixed, i got a 36G with a 10G sump
Depends on what you have planned for the tank.
If you're going for the typical overstocked "garden" reef, then I would not suggest the 9002 (a venturi skimmer) for anything larger than ~25 gallons or so. Otherwise up to about 40-50 gallons would be handled.
They've released a new nano needle-wheel skimmer -
the 9004 ($150) - which should handle your tank nicely! Tunze is recently a R2R sponsor, so you could drop in on
their forum here and see what they have to say as well!
BTW, will you have enough water depth in the sump to handle these skimmers? As in-tank skimmers, both the 9002 and 9004 are designed to sit in around 9" of water. Either will be fine in the sump as long as you can meet this requirement.
My favorite alternative might be to deploy an Aqua C
Remora (hang on) or Urchin (in-sump) on that system. Very simple, well designed skimmers that offer great bang for the buck - especially since they are not hard to find used. (Especially the Remoras, but also with some patience the Urchins.)

They also allow you to use any utility pump you'd like - more/less efficiency, expense, flow at your discretion. Most people start out with 300-350gph and have great results.
Good luck!
-Matt