can anyone tell me if theres is any chance to run it with a 520 gph pump that i actually have???

which are the risks for running it with a few less circulation that the recomended???

the thing is, here in town, take a long time to find pumps bigger than 450 gph...

2 years in the hobby, 70 gl reef aquarium, sps and lps, Deltec Ts 1060, Pacific coast 1/6 chiller, HM 250 w Radium 20 K...another 75 gl tank for softies with Remora Pro and Curretn Satellite 2 x 96 lights

I apologize for the delay in responding.

IMO I would not run it with the 520 gph pump you have.  By the time you figue in head pressure that may drop the pump into the 300-400 gph range which is a quite a bit lower than the minimum flow rate.  I don't recall exactly what can happen, but I believe it may not allow the chiller to properly read the water temperature (when using an internal controller).

You may want to call Pacific Coast or send them an email to double check what would happen going under the minimum flow rate.

Sorry I couldn't be more help on this.

________________________________________________

Keith

"Simply put, you believe that things or people make you unhappy, but this is not accurate. You make yourself unhappy." Wayne Dyer