Hydor Koralia 3's, 2 too many for a 40g tank?

[DanG]

I'm looking at upgrading the flow in my tank. As is, I have 2 seio 620's in there. Would going from 1240gph to 1700gph in a 3 foot long tank be too much? I'm not having any problems with buildup, and the 620's aren't creating any sandstorms, but don't want to stress my inhabitants by just adding all this extra flow. I've got a softball sized colony of both frogspawn and candy cane coral, one lonely acro and 2 GBTA's. A couple of chromis, a maroon clown, a 2 inch foxface and a bunch of snails and crabs.

Too much? Should I be looking at the Korila 2's?