Good luck with the rock collecting audio. I've done my share around the Sierras and haven't found any rocks like these yet.
I gotta try because I don't have your connections and Japan is bogarting what is left from what I've read. There are some pretty cool looking rocks up in the hills and mountains here in S. Ore. The Siskiyou mountains are particularly interesting geologically and botanically. Lots of granite, marble and other metamorphic rock. Might as well snag some Manzanita while I'm up hiking around.
This: CFS 500
Soooo much better than my Eheim Pro3 POS
I just looked on E-bay and the Odyssea CFS 500 was a reasonable $60. What was bad about the Eheim?