Right now I use a solid copper CFC and pump to chill. Even with a pre-chiller, I'm having a hard time getting anywhere near pitching temps with our 86 degree ground water. This typically isn't a big concern as I can cool it down pretty quick in my fermentation fridge, but I'd like to do it quicker to preserve aroma in my late-hopped beers.
I've read that whirpooling/recirculating around an immersion chiller may be a quicker method, but would have to significantly modify my setup to try it. Plus, with my groundwater temps, I'd need a pre-chiller for that....
Any silver bullets here that I've overlooked? Besides glycol, of course.