MJ1200 as return for sump

[andsoitgoes]

Okay - so I'm getting a WEE bit of conflicting info and wanted to pass this around to the "Masses".

I'm really into getting my sump up and giong this weekend, in this post, I have pictures of what my sump design looks like:

http://www.canreef.com/vbulletin/showthread.php?t=30003

I've had a few people mention that I can just cap off the outflow bulkhead, and run a MJ 1200 with a standard clear tube, as it wouldn't be possible (from my understanding) to put the 1200 into a return tube, it's just too small. The sump is 24l x 16.5h x 12w, approx 21g (I know, odd size..)

However, doing the calculations on ReefCentral, it's telling me that at approx 2 feet, with no bends/connectors/etc - I'm going to get a whopping 53gph flow... That's just over 1x, which I'm sure wouldn't be HORRIBLE, but I figured I'd get at least 100 or so GPH. Seeing another thread on here that talks about the GPH recommendation of 10x/hr or more, I'm concerned. Should I run 2 MJ1200's and again, just forego the bulkhead?

Thanks in advance!!

Nick